God's Love for You is Unique. God's Law is Not. Don't Demand Miracles.

Several times in the Bible, God intervenes to save people. From manna in the desert (Exodus 16) to Paul's shipwreck survival on Malta (Acts 27), these stories are told and retold, sometimes assuming that the main teaching is that God's chosen ones lead a charmed, shatterproof life. This approach to faith has led several Christians to argue that we should shun masks and vaccines, because God will save us.

This has led to death in several cases, some with high-profile public figures, many more unknown to us. Many people who've assumed they are immune to Covid have died. But even if God hasn't protected thousands of other people, God will still protect me, so I shouldn't try to protect myself - isn't that what the Bible says?

Time and time again, God's care for us is not a supernatural intervention, but a command to follow. God doesn't build the ark: Noah obeys and builds the ark (Genesis 6). God calls Abraham and Sarah to leave their homes and embark on a long journey (Genesis 12). God reveals the meaning of Pharaoh's dream to Joseph, and amazingly, Pharaoh listens to this foreign prisoner, and the people comply with his instructions to build granaries and collect food (Genesis 41). Yes, God sends plagues upon Egypt to support Moses' demands for Israelite freedom, but not while Moses stays on the sidelines expecting miracles: instead, God's first intervention is to demand that the reluctant Moses take action (Exodus 3), and gives Moses further orders throughout. Consider the manna story itself: most of Exodus 16 is about the instructions that come with the manna, about how much to gather when, how long to keep it, and pitfalls of noncompliance. The Exodus story continues straight to Mount Sinai, the Ten Commandments, and the beginning of the Law.

Expressing our faith by following instructions rather than demanding miracles is particularly explicit in Biblical passages about disease. In the story of Naaman's healing with Elisha (2 Kings 5): Naaman, an Aramean general, travels far to see the great prophet of Israel, and is indignant when, instead of calling on divine intervention, Elisha tells him to bathe seven times. But it works, and Naaman is led to a deeper understanding and commitment as a result.

Rules for how to behave in the face of disease are given at length in Leviticus 13-15, including quarantine periods and sanitation rules for clothes and houses after infections. It's worth dwelling on these chapters, because this is the place in the Bible that talks most about disease in terms of public health legislation for all times, rather than narrating a particular event. If infected, you must appear before a priest for examination. Chapter 13 lists several symptoms for the priest to check, and timelines for when to check again to see if the infection has cleared. The word "leprosy" or "leprous disease" is often used in English translations for historic reasons, but the symptoms described, the possible timelines for recovery, and the detection of disease in clothes and buildings indicate that the Law isn't talking about leprosy in the modern sense, and may have referred to a variety of skin infections. If you test positive, the rules are strict:

"Anyone with such a defiling disease must wear torn clothes, let their hair be unkempt, cover the lower part of their face and cry out, 'Unclean! Unclean!' As long as they have the disease they remain unclean. They must live alone; they must live outside the camp." (Leviticus 13:45-46).

So healthcare status is not private information, freedom of movement is curtailed when preventing the spread of disease, and the Law can dictate when to wear a face covering. We don't know precisely what disease motivated these regulations, but we do know that there was serious illness, and that individuals did not have an "inalienable right" to go anywhere wearing anything: personal freedom in time of sickness was subordinate to the Law that protected the community.

We are left with a very clear picture of where the ancient Law stands with regard to public healthcare mandates. They were in place. God's commandment was to follow the Law, not demand personal exceptions.

This leaves the tempting claim that this was for them: it doesn't apply to us. One may argue that ancient Israelites may be forced to cover the lower part of their face, but not modern Americans. Irrespective of whether we support this argument, I hope we can at least all agree that it is a nationalist, not a religious objection.

So perhaps we can argue that even if public health mandates are part of the Law, that is the Old Testament and doesn't apply to Christians. (It is easy to find parts of the Law that we never follow nowadays, for example, instructions on animal sacrifice.) So maybe Jesus says we should trust God's direct intervention rather than instructions on health precautions?

One of the times Jesus heals a leper, the next thing Jesus tells the patient is to "go and show yourself to the priest, and make the offering prescribed by Moses" (Matthew 8:4). Jesus himself reinforces the community rules discussed above.

In the Gospels, Jesus does encourage us to trust in God's care. "Consider the lilies" (Matthew 6:28, Luke 12:27), "Take nothing with you for the journey" (Luke 9:3). But not with the promise of supernatural miracles: with instructions to find people along the way who will help ("Whatever town or village you enter, search there for some worthy person and stay at their house until you leave" Matthew 10:11). Practical preparation is sometimes mandated. The whole parable of the bridesmaids is about this: they should all make sure that their lamps are well stocked with oil for a wedding, and those who don't bother are left in the cold (Matthew 25). They don't get miracle oil instead. Yes, Jesus commands us to free ourselves of worldly concerns: but following "Consider the lilies", the instruction given is not "Take any risk and don't let anyone else tell you what to do" - it is "Sell your possessions and give alms" (Luke 12:33). The notion that faith in Jesus saves us from earthly troubles is dispelled by Jesus himself: "Then they will hand you over to suffer and will kill you, and you will be hated by all the nations because of my name" (Matthew 24:9). If we reckon this suffering is intended metaphorically but not physically, the persecution of Christians in the Acts of the Apostles dispels that. Belief in Jesus doesn't shield us from physical harm: Jesus' own physical sacrifice was not to guarantee our physical invincibility, but to share something much deeper.

When St Paul says that the gifts of the spirit include miraculous powers, this is with the understanding that the Spirit distributes these gifts "according to his choosing" (1 Corinthians 12:10-11). This is clearly not advice to count on miracles and ignore practical instructions. Foolhardy decisions that demand a miracle to save us are born of hubris, not faith. Jesus addresses this point exactly in the Temptation in the Wilderness (Luke 4) - when tempted to cast himself down from the pinnacle of the temple because God will save him, Jesus answers "It is written, You must not put the Lord your God to the test" (referring to Deuteronomy 6:16). When a voice says "Take whatever risk you like, God will save you!", remember that Jesus rejected this advice as devilish not divine (Luke 4:11).

There is another related argument made against face masks and vaccines: God made us in his image, therefore our bodies are perfect, and any attempt to interfere with them must be wrong. From a New Age perspective, this is defensible (albeit irresponsible). From a Biblical perspective, it's simply wrong. If human bodies are perfect and shouldn't be tampered with, then God's chosen ones from Abraham (Genesis 17) to Jesus (Luke 2) were wrong to be circumcised. Obviously the Bible does not teach this.

In the Bible, faith isn't demonstrated by refusing to act and by demanding miracles instead, but by following God's commands, often delivered by other people. Biblical law and modern secular law both agree that where we go and what we wear can be regulated, for the safety of the community. And in the Bible, that sometimes includes face coverings.

Let's Sing About the Lovely Rain!

At the moment we talk a lot about language and bias, and a lot about the climate and weather, but we rarely talk about these together. The next couple of days will be the hottest on record here in the Pacific Northwest, and it makes me wonder about this.

The overwhelming bias in the songs I know is that sunshine is good and rain is bad. Perhaps this is typical in lots of places? Or maybe I have biased sample rattling around in my head?

To check something slightly more general that my own memory, I found these two playlists on the same music site:

Songs-About-the-Sun-and-Sunshine

Songs-About-Rainy-Days

Take a look and you'll see an overwhelming correlation between sunshine and good times and between rain and bad times. Not every song - there are some songs that express some fondness for the rain, or something that happened while it was raining - but the trend is clear.

I wonder if this trend holds throughout other musical traditions? Or is it another way in which cold wet parts of the North Atlantic are dramatically overrepresented? (Side note - in the myth of Persephone and Hades, we just assume that this corresponds to northern Europe's summer vs winter myths, but some return of fertility celebrations were late autumn when it starts raining, not when it gets warmer - see e.g., Thesmophoria.)

Either way, with increasing heatwaves and droughts, we should change the way we think about this! I don't expect that singing more songs in praise of rainfall will persuade the rain gods to rain on us - but I do think that we should be more aware that too much sunshine can be devastating, and freshwater that falls from the sky is a life-giving treasure.

Surge Pricing, Artificial Intelligence, and Responsibility

On my first work trip to Jakarta 14 January 2016 for Grab, multiple terrorist bombs exploded a couple of miles from the GrabBike office where I had just arrived. People were fleeing cafes and restaurants around the attack site. My new colleagues were shaken, glad to be safe, looking to help. There was news of crowds on the streets trying to get away, confirmed by a spike in booking requests from the blocks around the explosion. My colleagues remembered the 2002 Bali bombings, and knew we should get people to spread out. And we knew that our algorithms would treat this like rush-hour demand and activate surge pricing. People needed to be evacuated, but left to its own devices, our AI would have discouraged them with a higher price.

We should make trips away from the surrounding blocks free.The whole staff (including Anthony Tan, the CEO) were clear on that goal. I don’t know how many app notifications, vehicle type configs, price settings, promo code workarounds, driver incentives, press communications people set up - but they figured it all out, leaping into a sudden disaster response situation in the space of a few minutes. And it worked.

In Texas right now, a week into a freezing natural disaster, we’re hearing of customers being charged 75 times the normal rate for electricity (average is about 12c per kWh, the peak was set at $9). At this price, the average US household would pay around $8,000 a month for electricity. Instead of just canceling this, there are various proposals for the state or federal government to provide “disaster relief” by paying such bills. Or maybe the next step is a class action lawsuit.

This is not just an absurd failure of government in its lack of planning, regulation, and incentive setting. It’s a cowardly attempt by the private sector to profit from its own ineptitude. If not by malice, then by unaccountability.

I learned more about surge algorithms at Grab, partly because pricing and discounts were closely related to my work launching GrabShare. As data scientists and engineers, we had a duty to help make pricing equitable for passengers and drivers. Topics included nonlinear surge, geographic smoothing, time-of-day buckets, price elasticity, featurization, and machine learning. None of these are silver-bullets - they are tools in a system that also includes many human-oversight safeguards. These safeguards include basics, like hard limits on surge price multiples - these vary from city to city, but to give you a sense, we’re talking about numbers like 2 and 3, not 75 or 100. We have clear rules about price stability and guarantees - if we quote a $10 ride, the passenger gets a $10 ride. If that price in the meantime becomes inequitable for the driver because traffic and demand is up and the surge is larger, then the system messed up and we need to fix it. We don’t pass the buck (or the bill) on to the passenger in the meantime.

Equitable pricing isn’t just applying a known set of rules, it’s a practice of thoughtful and watchful diligence. This is increasingly crucial in AI where it is everyone’s responsibility to anticipate and prevent unintended consequences. A typical example - of course we had the idea of using destination as a feature for predicting an acceptable surge price. This came up as a suggestion so many times that a hypothetical “hospital example” became a repeated reminder - we would never build a system that might “learn” that people whose destination is a hospital tend to be willing to pay higher fares. The claim that “nobody really understands how AI systems make individual decisions” would be a lie to hide behind: when we properly stop and think when adding a new feature to a machine learning algorithm, we can normally come up with hypotheses to test quite easily, including bad outcomes that must be prevented.

Those are just some of the ethical considerations within AI and machine learning and only one part of an organization responding to a crisis. During Grab’s Jakarta bombing response, the automated pricing surge algorithm was just switched off - we knew that part would do harm. For those few hours, business-as-usual was no more, and it was mainly the finance, promotion, and driver operations leaders scrambling to improvise together. The office went from confusion to celebration: high-fives as we heard the first reports of passengers getting away to safety; press reports that our rival Go-Jek had joined us in the effort; that day we were all working together and it was working. And of course, the commitment this inspired in me about Grab was incalculable.

Contrast this with what we have heard about electricity providers in Texas. The surge was allowed to skyrocket up nearly 100-fold, just when people needed power most to survive. Some may argue “that’s how market forces work”, as if that makes the outcome right rather than making the design wrong. Ambulance drivers are often in situations where people need them desperately - but “market forces” don’t make it ethical to charge injured people 100-times the going rate for an ambulance ride. There may be some who argue that an auction rather than medical risk should be used to prioritize people for a scarce vaccine. Most of us disagree.

So what we’re left with instead is the excuse of organizational helplessness. “Nobody wanted it this way, it just happened.” That’s rubbish. Someone has a password to a database and could go in and cancel those outrageous bills right now. There are heads of department who could demand such action and answer to their CEO. There are CEOs of energy companies who could have ordered on day one of the disaster “We provide an essential service that people need to survive: bills will be cancelled and payment figured out later when it’s safe”. They haven’t done this yet. Instead we’ve heard politicians say they’re trying to figure something out - even including using disaster relief money to line the pockets of these companies.

Wake up, American businesses. This isn’t about “preventing socialism” or “the sanctity of market forces”. Don’t treat your customers as hostages. That’s evil, and companies that do this will ultimately fail. Businesses are not just lowly enforcers of runaway algorithms, so don’t pretend that we are. If anyone reading this can implement proper remediation steps for any of the power companies involved: please seize this opportunity. You can be a private-sector hero today.

Christian Homophobia: Hypocrisy over the Bible and Secular Law (again!)

Earlier this week, the Supreme Court of the United States ruled that companies can't discriminate against people based on their sexual orientation. Several self-professed conservative Christians have complained, typified perhaps by Franklin Graham, son of the famous evangelist Billy Graham, who said "People of sincere faith who stand on God’s Word as their foundation for life should never be forced by the government to compromise their religious beliefs."

At least two objections to this should be obvious, but seem to be rarely talked about.

Firstly, if "standing on God's Word" means "following the Bible literally", then people are forced by the government to compromise their religious beliefs the whole time. As an obvious example, consider Leviticus 20:10, "And the man that committeth adultery with another man's wife, even he that committeth adultery with his neighbour's wife, the adulterer and the adulteress shall surely be put to death." (KJV). In the United States, you are allowed to believe this - because one of the great benefits of religious freedom, you can't be persecuted for believing or not believing something. But you are certainly not allowed to carry out the threat - it's murder, and the claim that a particular belief led you to commit murder is no defense. The Supreme Court decision says that the same argument applies to firing someone because you discover that they're gay. It's legal to believe that they shouldn't be gay, but it's not legal to fire them.

Secondly, we should once again confront the cherry-picking hypocrisy of Biblicist homophobia. The level of discussion here is typically poor: someone whose stance is largely anti-religious is likely to point out that the Bible also bans tattoos, the eating of shellfish, or clothing made from mixed fabrics; someone who's been taught to defend Biblical homophobia says that those other laws are obviously ceremonial; there is no meeting in the middle, no real discussion. Or someone whose stance is more liberal-religious points out that some of the words translated as anti-gay are quite ambiguous, like the debate about the word "ἀρσενοκοῖται" ("arsenokoitai") in 1 Corinthians 6:9, which could refer to pedophilia, and has only been translated as against homosexuality for less than a century. But quibbling over a word in translation never really helps (it might convince someone who won't learn any Hebrew or Greek that educated pen-pushers are out to trick them). Picking particular words to focus on, or particularly outdated verses as a compare-and-constrast, doesn't make for much of a discussion.

However, looking at the (actually very few) anti-gay verses in the Bible in their surrounding context does reveal a much clearer picture of cherry-picking. Take the Leviticus 20:10 example above - punishment for adultery. It's just 3 verses before the condemnation of "man lying with man", which is quoted much more often. And it's part of a whole list of taboos, particularly against adultery and incest, and followed in the next chapter with a ban on marrying a divorced woman. Or the passage in 1 Corinthians 6 - the very same list that condemns ἀρσενοκοῖται also condemns πόρνοι (pornos) and κλέπται (kleptos). It's pretty clear what those mean - the author condemns pornography and theft. One of those is illegal in the USA, one isn't (though it is in several other countries). Taking the Bible in context, the passages of laws and punishments in Leviticus are often arranged as more detailed working-out of the laws given in the Ten Commandments (Exodus 20 or Deuteronomy 5). The clear sexual commandment is "Thou shalt not commit adultery", and the subsequent passages banning incest, homosexuality, remarriage after divorce, and so on, are arranged as matters related to this. Passages against homosexuality are few, ambiguous, and always placed alongside other condemnations. Passages against adultery are frequent, repeated, used as the basis for other condemnations, and have their own dedicated place in the Ten Commandments.

So, if Mr Graham and his allies were to demonstrate that they believe adulterers should be persecuted at least as much as gay people, then they would be giving more than lip-service to their claim to follow the Bible. But they won't. They are homophobic hypocrites, preaching selective bigotry in place of equal justice, degrading the Bible by weaponizing verses and ignoring the chapters and books from which they come.

Questions Asked Later

Adding a Q&A section of things close friends and family have asked so far.

Aren't you saying that homophobic beliefs are OK?

Not OK: just not illegal. Personally I detest homophobia. But I wouldn't introduce an Inquisition or a Thought Police to make sure those beliefs can't exist.

Isn't there more context about Corinth behind Paul's letters?

Yes. There's plenty of discussion about what the contemporary practices were and whether Paul was condemning committed relationships or licentious parties.

Are you saying that homosexual relationships are as bad as adultery?

Personally I don't think that homosexual relationships are anything at all like cheating on a partner. I am saying that if someone is really following the Bible, they can't honestly condemn homosexuality without condemning adultery at least as strongly.

What about the Biblical bans on working seven days a week, lending money and charging interest, bearing false witness, and so on?

Quite right. If we made a complete list of practices banned (and punished) in the Bible with notes about how often they're mentioned and how harshly they're punished, that would be a very long essay. The reason I focused mainly on adultery in this essay is because it's the ban in the Bible that's most clearly related to homosexuality - the Bible discusses homosexuality as a footnote to adultery. If you want to investigate this area more generally, start by reading the Ten Commandments themselves and ask "Which of these would we recognize as laws today?" It is a very interesting mixture.

Why do you think that the very same Christians who denounce homosexuality give a free pass to leaders who practice serial adultery, abuse, financial fraud, and lying?

It's not about Christianity and the Bible really, that's just an excuse. (I'm sure they do believe it's about Christianity and the Bible, though you can't keep believing that if you read the Bible honestly.) It's about being angry and afraid that the world is changing, and the sort of people who for centuries were in charge (wealthy white European and American men) might not automatically be in charge in the future. This is frightening, and when things frighten us we're all predisposed to say that they're morally wrong. It's not about being in any way harmed by gay people: it's all about being frightened that they might no longer be the arbiter of who gets a free pass in spite of hurting people, and who gets persecuted in spite of hurting nobody. Never expect people to be rational when they're scared.

Why do you care so much about the Bible and homosexuality?

I'm a Christian, and I care passionately about the religion that motivated the spread of literacy on several continents, the founding of schools and universities, the abolition of slavery, parts of the Civil Rights movement. The history of Christianity isn't all good, but it certainly has good parts. I don't want to see its future potential ruined for generations by outdated bigots using it to defend their own personal bigotry.

Courage and Cowardice before Angry Crowds

In May 2020, Donald Trump, President of the USA, used riot police to remove protestors, clergy, and laity from the way to St John's Episcopalian Church in Washington DC, so that he felt safe enough to leave the Whitehouse without having to meet any of them.

During the Peasants' Revolt in 1382, King Richard II, then 14 years old, met crowds of rebels in person at least three times. Though some of the most violent leaders were executed, the King personally diffused some of the angriest crowds, and acknowledged and met the demand to abolish serfdom. (For all of us who've ever left a bad employer by applying for and getting a better job, we owe thanks in part to the eventual success of the Peasants' Revolt.)

In 1897, Sarah Alexander saved Gandhi from a white lynch mob in Durban, keeping them at bay with her umbrella, until her husband (who happened to be the chief of police) responded to her summons and came to join the rescue. Were it not for Ms Alexander’s bravery, the modern history of India would be entirely different.

Nell Gwyn, famous actress and mistress to King Charles II, was once beset by a mob in Oxford. Thinking they were mistaking her carriage with that of an aristocratic French rival, she put her head out of the coach and called "Good people, you are mistaken; I am the Protestant whore!” Of course, I’d expect to be sorely castigated for using such insults today - but golly, she had wits and she had guts!

These stories inspire us. They show us heights of courage and leadership in the face of an angry crowd.

By contrast, a leader who cannot even bear to listen to an angry crowd is a coward. A leader who needs armed bully-boys to clear the way before they dare to venture out is literally a fascist - the “fasces” was the bundle of rods with an axe blade that was carried by the lictors, a magistrate’s bodyguard in Ancient Rome. Don’t take the etymology too literally, I’m not saying that the USA is now by definition a fascist dictatorship. By the same token, “democracy” doesn’t literally mean “mob rule” anymore, and someone can be “ostracized” without writing anything on a broken piece of pottery. But definitions aside, President Trump’s acts of bullying deserve our scorn and disgust, especially when so easily contrasted with historic acts of bravery and leadership that so naturally inspire our humble praise and respect. We can tell what a coward looks like, because we know what a hero looks like.

- https://www.usatoday.com/in-depth/graphics/2020/06/05/george-floyd-protests-trump-church-photo-curfew-park/3127684001/
- https://en.wikipedia.org/wiki/Peasants%27_Revolt
- https://www.outlookindia.com/…/when-mahatma-gandhi-…/1629866
- https://en.wikipedia.org/wiki/Nell_Gwyn

The Peasants' Revolt, also named Wat Tyler's Rebellion or the Great Rising, was a major uprising across large parts of England in 1381. The revolt had various causes, including the socio-economic and political tensions generated by the Black Death in the 1340s, the high taxes resulting from the conf...

Wildfires or Cats - What's the Bigger Threat?

In the past couple of weeks I've seen figures saying that 1 billion animals have been killed by fires in Australia ... and figures that say that every year, "free-ranging domestic cats kill 1.3–4.0 billion birds and 6.3–22.3 billion mammals annually" (Nature Communications, 2013) in the USA alone.

So every year, cats in the USA might be responsible for more than ten times as many animal deaths than this year's devastating fires in Australia.

Personally I quite like cats. I wish they wouldn't take birds, but at least in our neighborhood, we have a much bigger problem with rabbits - so for the sake of tulips, crocuses, grape hyacinths, and many other plants, I think the cats might be helpful. (Sorry, bunny lovers, I don't mean to horrify you.) But who knows, maybe even keeping the rabbit population under control is a job best left to native predators. However we see it on a neighborhood level, introducing a predatory species that kills billions and has few if any predators of its own doesn't turn out well for ecosystems.

If we really want to save wildlife, many of us are right behind initiatives to curb greenhouse gases, plant trees, restore habitats, and if it's done carefully and well we are willing to pay for this with taxation.

But if we wanted to save ten times as many wild animals, do any of us have the heart to tackle the cat problem? If not, the easily-repeated finger-pointing "Science tells us how to solve the problem but you just refuse to, that's irrational and immoral!" comes right back at us.

Frequently Asked Questions and Discussion Points 

There have been a few responses to this post, which I'll try to gather here. (Feel free to post comments and corrections, especially if you think any of the points below are not presented fairly.)

Are you saying that wildfires aren't a problem?
Of course not. For Australia particularly, I recommend donating to https://www.rspca.org.au/. 

Feral cats are the biggest problem, not pet cats

In terms of numbers, the Nature Comm. article agrees: "The predation estimate for un-owned cats was higher primarily due to predation rates by this group averaging three times greater than rates for owned cats." This argues that controlling the feral cat population is more important than convincing cat owners to keep pets indoors.

Cats have always been part of the natural ecosystem

That's true on most continents, though not Australia and many islands. But the scale of the problem is unnatural. If one-third of human households kept foxes as pets, and every year some proportion or these foxes returned to the wild and bred, then the sheer numbers would cause a similar problem for other species. Similarly, fires have always been part of the natural ecosystem, but the ways human activity interacts with the environment can make them more devastating. Fires are natural, but still devastating, and if anything it makes it even more crucial that humans follow responsible policies that take this into account.

Deforestation and pesticide use on a mass scale are far greater killers of native wildlife than free roaming cats

Again, from the Nature Comm. article: "Our estimate of bird mortality far exceeds any previously estimated US figure for cats 13,14,16, as well as estimates for any other direct source of anthropogenic mortality, including collisions with windows, buildings, communication towers, vehicles and pesticide poisoning 13,15,16,17,18,19,20,21." 

So there's a big list of citations to the contrary. It includes a range of studies going from 1979 to 2012, and it's not easy to compare "apples to apples", so I dare say that it's possible and valuable to do further studies. But with the information I have at present, I don't have a good alternative to accepting that cats kill more than pesticides.

Are there other articles that corroborate this research?

https://www.frontiersin.org/articles/10.3389/fevo.2019.00477/full

http://www.ace-eco.org/vol8/iss2/art3/
https://doi.org/10.1093/jel/eqz035

Omnivores have to kill to survive ... I find the Australian fires more disturbing because lives were lost en masse for nothing.

Yes, absolutely the recent fire events are disturbing beyond belief. And it's notoriously hard to feel an empathic connection with long ongoing events, compared with immediate catastrophes. There is a core emotional difference here - it's easy to want to reduce fires, or diseases, we have little or no emotional sympathy with bacteria, let alone fires. It's hard to frame a policy for controlling cats without feeling that it's grossly inhumane to blame them for being themselves, whereas we don't feel that we're "blaming" fires or bacteria for anything - we don't feel that they're advanced enough evolutionarily speaking to be "blamed" at all. 

Cats should not be demonized, this leads to cruelty
Absolutely. There should be no place at all for feeling revulsion towards cats themselves. It is really bad that anger against cats can lead to inhumane or cruel treatment.

What's a "humane" way to control feral cat populations?

• According to this article, approved forms of poisoning: https://www.environment.gov.au/biodiversity/invasive-species/feral-animals-australia/feral-cats
• They work with the RSPCA to some extent, though agreeing that a poison is "more humane" might not be the RSPCA saying that it's "humane"!
• The alternative "trap, neuter, release" (TNR) programs have been shown to be ineffective at reducing feral cat populations. See https://abcbirds.org/program/cats-indoors/trap-neuter-release/
• Of course, there are still strong advocates for TNR. However, it's worth noting that all the articles quoted by this advocacy site measure the sizes of particular cat colonies and the health of these cats, not the whole population over a larger area, or the affect on species other than cats. See https://www.alleycat.org/resources/trap-neuter-return-research-compendium/
• Each of those pages have many links to research. Core problems with TNR cited include the fact that it doesn't take many breeding adults to keep populations up, and a healthy neutered feral cat is still living out its life preying on other animals.

Surely introducing poison to the food-chain is a terrible idea?

It usually is. See https://www.environment.gov.au/biodiversity/invasive-species/feral-animals-australia/feral-cats? for ways poisons in Australia at least have been carefully designed not to harm native wildlife (based on genetic resistance or even different chewing behaviour).

Cats have a right to live just as much as other animals
Cat's don't have a right to be introduced in unnaturally large numbers into new ecosystems and wipe out entire species.

It's wrong to kill cats
Yes, and it's a choice between the lesser of various evils. So it's a kind of trolley problem. But it's a particular case where we humans made the trolley, we are guiding the trolley, and we can see that if we do nothing we're preferring the uncontrolled spread of cats (of which there are already many) over entire species (which are irreplaceable). It's wrong to kill cats, but it's even worse to introduce them, let them kill entire species, and then say that doing anything more about it than neutering some of the cats would be immoral.

Why do we treat dogs differently?
We've been culling / euthanizing / removing stray dogs all over the world for years, because packs of stray dogs are much more of a menace to humans, and because they're a menace to humans, we regard population control as a necessary evil. Of course, it's not that simple, there is a huge variety in ways dogs have been treated, sometimes tolerated, removed, there are similar no-kill policies in some places that people advocate for cats. For a survey of dog population management and its relationship with rabies, see this article. It finds that indiscriminate culling is counterproductive (as well as undesirable), but acknowledges that for unowned dogs, euthanasia is the only way currently available to reduce overcrowding in shelters. Just neutering and releasing stray dogs back into wild or urban environments is hardly ever advocated by anyone - to the extent that this suggestion would be considered ludicrous. It is however very much what we sometimes advocate for cats. The difference between our policies for dogs and cats is based on their size relative to humans - a poor way to make decisions for the host of other species.

Massacres and Martial Law

Spurred by the thought of the "St Valentine's Day Massacre" in 1929, when seven Chicago gang members were shot - when such events are from a different time or place, we don't call them "mass shootings", we call them "massacres". Opponents of stricter gun safety laws are saying that it's either pointless or undesirable to use gun safety legislation to prevent massacres.
In other countries, when executives in power get so frustrated with the civilian legislation process that they order military funding and personnel to be used for domestic law and order enforcements, we don't call it "using emergency powers", we call it "declaring martial law". That's how we would describe President Trump's actions today if he were the president of another country, unless it was at war or in the immediate aftermath of a natural disaster.
If your quick reaction to that description is "Calling this martial law is ridiculous, you're blowing this out of proportion!", please ask yourself where that reaction is coming from. If we really believed that immigration at the US / Mexican border is an emergency threat to basic law and order, a threat to our immediate safety, we would sadly acknowledge that declaring martial law is a necessary evil. Nobody seems to actually believe this - certainly, nobody has said "The situation is so urgent, President Trump is right to declare martial law". In other words, using "martial law" is out of proportion - but it's not the name, it's the decision itself.
I suspect a lot of people's discomfort with the term martial law is because, while it's easy to feel that the President is wrong, it's very hard for many Americans to feel that Democrats might be right. That's a nasty emotional dissonance, and it makes us want to ignore what's being done on our behalf. That's one of the ways that democratic rights are lost.
If you have Republican representatives with any influence here, please tell them that you think the military should not be used to circumvent the civilian legislative process for raising government revenue in this way. Such a belief, after all, is what the American Revolution was based upon. And please ask your friends and family to consider these issues.

The College Captain

In the midst of many stories of youthful drunkenness and its bad consequences of sexual assault, I’d like to share a story from the early 1990s. We were in college, undergraduates at Durham, and I remember a small crowd milling around in a bright stairwell after the bar had closed. Most people were somewhat drunk, and some were very drunk, which was normal.

My memory is incomplete - I remember the exact place, but not the date. I couldn’t tell you how many people were there. But I do remember the two main characters in the story, even though I only remember one of their names. He was a true college sports captain - good looking and very popular. The girl was blonde, and I think I remember she was wearing a charming red cocktail dress, from which I’d guess that this was after a formal dinner or college event somewhere. The sports captain had been flirting with her earlier, I think - at least, we’d been teasing him at times about what his chances were with her this evening.

By this point in the evening she was blind drunk. Really really intoxicated - shaky, slurring words, flopping around while trying to stand up. As they kept talking on the landing at the top of the stairs, she was flopping more and more in his direction. This went on for a while, and soon he was practically holding her up. They could easily have left and spent the night together - that kind of thing was relatively common.

What happened next was different, and surprised us. What I think I remember is the sports captain getting the attention of one of the girl’s friends, who came over. After a brief conversation, a few of the girls left together, taking their staggering friend along with them. The sports captain moseyed down the stairs to join the rest of the crowd.

The teasing started over again. Much of the conversation I’ll just guess at and reconstruct. “What happened there?” “Well, it was time for her to go to bed.” “But you’ve been chatting her up all night, and we thought you were in!”, “Oh mate, you just blew it!”. Typical banter.

His response took us by surprise.

“Come on, boys, you could only see the whites of her eyes. There’s no honour for anyone in that!”

That’s the moment that stuck with me. This was already someone I looked up to, and I remember thinking yes, that’s what setting an example looks like, I’m lucky to be his friend.

An attack on all of us

This happened yesterday: Temple De Hirsch Sinai vandalized with anti-Semitic graffiti.

Since the election in November, at least one synagogue and two mosques have been attacked in my area. Since January there have been over a hundred threats against Jewish organizations alone.

We've also heard a lot about freedom of religion in the USA recently, which has sadly demonstrated that a lot of Christians think that being asked to write "Congratulations Mike and Tim" on a cake is unbearable, while a bomb threat at your daycare is just something Jewish kids have to put up with for being "different".

This is all wrong. So so wrong.

To my Jewish friends and family, so many of whom have connections with Temple De Hirsh Sinai, I am so sorry for this. Keep telling your story so we can all hear it and take action together. Let me know when you need someone to stand with you, if I can I will come.

To all my other friends and family and anyone reading this - we can see before our eyes how minorities are being attacked. If we let this happen, history will cast judgement on our inaction. If we talk tough on terrorism but allow white supremacist terrorists to operate unhindered, history will cast judgement on our bigotry. If we use our own faith to persecute others, history will rightly denounce us for being persecutors, not praise us for being faithful.

We must dedicate ourselves to using our voices, our checkbooks, our elected leaders, and our votes, and commit ourselves to turning back this tide of hatred.

Before the Women's March

Before heading to the Women's March in Seattle in a couple of hours, I'd like to share something that happened at work a few months ago. You might need to enlarge the picture, it's a bathroom scrawl, not easy to read.

There you go, simple and standard bit of sexist humor, scribbled in a "safe" place where the other people who see it are expected to agree, chuckle, and move on. As you can see, this time I didn't.

After scrawling my angry rejoinder, I shared the picture with my boss and HR rep, who were terrific. We were only a small company sharing the floor at the time, so we hoped it wasn't one of us - and I bet each of the other tenants hoped it wasn't one of them, and the building facilities hoped it wasn't one of them. The other tenants on the floor and building services were notified, and told their employees that the incident had happened, and if any more such behavior was encountered, there'd be a thorough investigation, and a culprit if positively identified could well get fired. Short of taking contortionist handwriting samples from every frequenter of the men's bathroom, I'm not sure what more they could have done. It seems to have sent the right message - at least, we haven't seen anything like this since.

Lots of us, women and men, will go to the march today. That's great. But not everyone can attend. Like a lot of parents, we're fitting it in for a couple of hours in between other commitments today. People have all sorts of reasons for being busy, and if you can't go, don't feel guilty. 

But for men in particular, what we do any other day is as important as what we do today. If we see something like the above and think "hey, it's just a bit of fun in the men's bathroom", then we're part of the problem. If we feel that somehow the real men like this kind of stuff, and it's only wimpy men that feel bad about it, then we're allowing ourselves to be part of the problem. 

Strong men don't demonstrate their prowess by disparaging women, or anyone else. They don't need to. If you want to be strong, stand up for others. Marching today is a great way to stand up. But there are no shortage or other opportunities, day by day. Most times the media isn't watching - the people watching are our friends, colleagues, and the hundreds of people we encounter in small ways as we go about our lives, in the supermarket, the parking lot, at the bus stop, on the sidewalk.

Men, do your part standing up for women. Logically it's just a special case of "people, stand up for other people", but social constructs make it a particularly important special case. Other people will stand with you given half a chance. Be gentle, be strong. Be a gentleman.

Searching e-mail headers is easy

(This is a very specific post about events deemed newsworthy at the end of October 2016, namely, the announcement that the FBI has reopened an investigation because emails found on a computer might be relevant to a previous case. For those that don't know me, I'm a software engineer who's worked at Google and Bing and written some dozens of papers about language and search, so while I don't know all the details of this particular laptop, I'm not just ranting without expertise.)

My professional opinion: the notion that the FBI may take days to figure out if some of 650K emails went through a particular server is nonsense. This is a one-line grep-the-headers command and may take as much as a few minutes on a standard laptop. Doing a more thorough preliminary analysis to see if a few individuals are mentioned by names or synonyms is a bit more work - maybe a couple of hours for a beginner programmer. More detailed topical analysis, now it's getting more fun - about a day's work for an NLP specialist using tools readily available for over a decade.

If you've read any "tech news" articles telling you that FBI agents might spend weeks looking for something vaguely AI-blabber sounding like "metadata", please realize that you're being deceived. The notion that this task takes days is utter nonsense. American readers and voters are being played and manipulated by claiming something is hard that is in fact easy.

From a language-processing point of view, the claim that James Comey had to notify Congress that they'd found a "big box of something" but it would take until after the election to have any idea of whether that big box contained anything relevant is incompetent nonsense.

If instead they're saying that out of those 650K emails, they have to read every one by hand because maybe, just maybe, someone-said-something-to-someone that could count as referring to something that was once at some grade of classification, then that's quite a different proposition. It's not a standard that is applied to any politician other than Hillary Clinton, and the notion that until you've done this you have "no idea what the box of stuff contains" is just not true.

At the very least, we should have a Director of the FBI who has beyond a mid-1980's sense of how hard it might be to search through fewer than 1 million email headers.

Epilogue

My this seems dated now. So as you probably know, a week or later just before the election the FBI reported that after all they didn't have anything new. Hillary Clinton went from a decisive lead in the polls to a dip in the polls, won the popular vote, but lost the presidential election. Given how close the elections were in the swing states that mattered, I suspect that history will tell the story of an election that was marred by scandal, and was decided in the end by the exact timing of when scandals were reported, real or imagined.

27% is not a Majority, and Leaving the EU Requires an Act of Parliament

Update some years later: The UK finally did leave the European Union on Jan 31st 2020. After 2 General Elections and several bumps in the road, the decision to leave was enacted by Parliament, and the particular worry that the referendum result might encourage Britain to ignore Parliamentary Sovereignty has been put to rest.

It's now a couple of weeks since the Brexit referendum. The question on the ballot was "Should the United Kingdom remain a member of the European Union or leave the European Union?" and a majority of the votes cast were for "Leave". Since democracy is the rule of the majority, and the majority voted to leave, some say that the decision to leave the EU has been made democratically, and any objections to this decision are anti-democratic sour grapes.

I disagree, and I've been asked (in this case, by my mother) to explain why I disagree. Here are the reasons why leaving the EU without an Act of Parliament would be both undemocratic in the short term and destructive to the UK's democratic constitution in the long term.

Of course, our constitution is unwritten, and so the process for changing it isn't formalised. We go by tradition, precedent, common law, and common sense.

The mandate for constitutional change is insufficient

In the referendum, 17.41 million votes were cast for "Leave" and 16.14 million were cast for "Remain". The population of the UK is 64.1 million (World Bank estimate). So about 27% of the population voted to Leave, about 25% voted to Remain. Moreover, the largest disenfranchised group (those under 18) would probably have voted strongly to Remain.

So the statement "A majority of the people voted for Brexit" is not true, not even close. If we had a formal constitution and an official process for changing it, I would wager that a popular vote of 27% to 25% would not be enough. (In the USA, for example, one of several conditions such as "ratified by three quarters of the State Legislatures" must be met.)

The campaign and result could probably not be repeated

We're used to election campaigns involving contested claims and exaggeration, but this one was extreme. This has been pointed out many times already, so I'll be brief. There's no £350 million a week coming back, immigration is not being curtailed, for those who wish to curtail immigration the path is entirely unclear, but the House of Commons has voted by 245 to 2 to guarantee that EU citizens living in the UK will have the right to remain. Given the obvious public unravelling of the Leave campaign's promises and its leadership, and some already clear economic damage, it is very unlikely that the referendum result could be repeated.

The referendum is not a mandate for a particular policy

In the weeks since the referendum, the UK's position is less clear than ever. It's clear that a deal with the rest of the EU to maintain free movement of goods but not of people is very unlikely, and that there are a baffling array of options in between staying in the EU and abandoning free trade between Britain and Europe altogether. The Leave vote is not a vote for anything except "not being in the EU". It did not set forth a particular option for relations with the rest of Europe, and almost every member of Parliament was elected on a manifesto that advised staying in the EU. The British people may have voted about something that's not wanted, but have not voted about what is wanted.

The only legitimate way forward involves Parliament

There isn't much precedent for using referenda in Britain, but what precedent there is says that referenda can be used in conjunction with Parliament, not instead of it. In the process whereby the UK joined the EEC in the 1970's (the only real precedent), the referendum result was much stronger (67% majority), but it was never used instead of passing laws in Parliament.

So far the only legal alternative to Parliament I've read about is the idea of using Royal Prerogative to pass laws relating to leaving the EU, apparently suggested by government lawyers. You don't need to be a constitutional lawyer to know that in theory the Crown can pass and rescind whatever laws it likes, but a monarch who does this in practice risks losing a Civil War, getting their head chopped off, and bringing down the monarchy. Of course I don't mean this as a threat, I certainly don't want it to happen! But the Queen is probably more aware of her role than anyone else alive, and the idea that she may make an exception from her well-known avoidance of politics and abolish an Act of Parliament without consulting Parliament, on an issue so controversial that England and Wales might go one way and Scotland and Northern Ireland another - well, even if that's legal it's still preposterous. If the government or the monarchy wants to nullify laws passed by Parliament, they have a perfectly legal and practical way of doing it - by asking Parliament.

This does leave the option that the Government might try to invoke Article 50 (giving notice of an intent to withdraw from the EU) without Parliament's consent, presuming that Parliament will cooperate later in repealing the 1972 European Communities act and many other pieces of legislation. But presuming that Parliament will comply with all this is a very risky alternative compared with asking first!

What if Parliament doesn't cooperate?

Let's briefly consider the reasons for not consulting Parliament.

•  Parliament might vote against triggering Brexit by invoking Article 50.
• It might. The alternative, "Don't ask Parliament because they might disagree", sounds utterly illegal and contrary to  Parliamentary Sovereignty, which is the very first principle of British politics.
• Parliament might vote in favour of triggering Brexit, but that's against the manifesto promises of most MPs.
• MPs are representatives, not delegates. If they choose to vote differently from their manifesto promises, that is legal and has many precedents.
• The Government needs to negotiate with other EU countries before it can bring a bill before Parliament.
• Nonsense. There is nothing stopping the Government from bringing forward a bill that asks for permission to negotiate.
• It might lead to enough controversy to bring down the Government in a vote of no confidence, triggering a general election.
• If the Government can't pass its most important legislation through Parliament, that's exactly what a general election is for. General elections are a costly, uncertain, and time-consuming process - but given that the whole Brexit process is already all of these things and more, the notion of doing something unconstitutional instead of holding a general election is crazy.

Can these arguments be dismissed as motivated reasoning? Something like "You wanted Remain to win anyway, of course you'll throw obstacles in the way of a Leave victory". Well, I do want the UK to remain part of the EU, but in this case that's not the point. The point is that overriding Parliamentary Sovereignty using an unlikely alliance between a 27% referendum vote and Royal Prerogative would set a terrible precedent. If the Government passes proper legislation to leave the EU, I'll be disappointed, I admit that. But if the bill is honest, properly worded, sensibly debated, and passed by Parliament, I'll be the first to accept its legality.

The Crown can be asked to dissolve Parliament, but not to ignore it. The people have the right to replace Parliament, but not to ignore it. These are the cornerstones of Britain's rather ad hoc but surprisingly robust democracy. It's not perfect by any means, but over the centuries it's done pretty well, particularly at avoiding the worst forms of oppression. Let's not give up our most cherished principles because of a narrow vote on a single day.

What should you do?

If you agree with this conclusion, please feel free to share and promote this article. But much more importantly for those living in the UK, write to your local MP. If you're below voting age, or a foreign national not allowed to vote in the referendum, they are still your local MP and you should write to them. This is not just for Remain supporters - if you're a Leave supporter, please write to your MP and say that Parliament should immediately put its authority behind the referendum result. This is one of those times in our history when Britain urgently needs Parliamentary leadership.

Why Britain Should Remain in the European Union

If I was voting with just my head tomorrow, I would vote Remain.

It should be enough that the UK pound and financial markets have taken a battering on just the fear of leaving. It should be enough that so many major economic leaders and institutions advise us to stay. That in spite of the popular myth to the contrary, actual data shows that immigrants are net contributors to the benefits system, not net takers. That millions of British retirees in other European countries are likely to be victims of Brexit, as well as younger working-age people in Britain. That stories about freeloading European countries taking Britain's money and Britain getting nothing in return are so easily debunked. That surveys demonstrate that "average British beliefs" about how much of our tax money flows to and from the EU are utterly misinformed. That I and my children can live and work in so many places from Ireland to Greece, and that's not something we would risk lightly.

But the referendum has clearly not been about voting with our heads. We're voting with our hearts as well. Would I vote differently?

The Remain campaign has looked lacklustre. It doesn't get people whipped up or nearly so passionate. As a parent I understand that: it's hard to make "Don't risk hurting yourself just to prove your independence" an inspiring message. If you show a picture of what hurting yourself might look like, you're scaremongering. If you don't, you're just being a wimp. But if I can explain that to a child about jumping down the stairs in a pillowcase, it shouldn't be so hard to explain it to grownups voting about their political and economic future. Perhaps my heart isn't immediately excited about staying in the EU. But is excitement really the point?

By contrast, the Leave campaign has looked ugly. Pictures of how wicked foreigners are. How we're being either overrun by underling dark-skinned swarthy types, or overlording light-skinned calculating types. About how everything is "us" versus "them". About how all the "them" must be kept away from "us". Not facts, not data, not research, not all the boring nerdy stuff that should go into actual policymaking. Just appealing to the idea that I should belong to a tribe, and feel threatened by every other tribe. The Leave campaign, and nearly all the material I've seen shared and circulated to promote it, does stir my emotions. It makes me ashamed that anyone would think that this is what being British should mean.

If I was voting with just my heart tomorrow, I would vote Remain. 

The Weakness of the Arguments Against Hillary Clinton

I've been staying mute on politics but I'm going to make an exception.

Wave after wave of anti-Hillary mouthing is gradually making me gently but firmly pro-Hillary. Just reading random news and other people's feeds over the past week I've heard all of the following arguments:

"She won't be able to win in all-important swing states."
Like Ohio and Florida?

"It's wrong that all those superdelegates are going to vote for her."
She's currently nearly 40% ahead in the regular delegate count.

"I have lots of friends who say they won't vote for her. Like really really won't vote for her ever ever."
That's not how national elections are decided.

"She sounds shrill."
The person behind the microphone should have a deeper voice - but it's not about sexism?

"She must be dishonest, look at all those investigations into her."
When investigation after investigation leads to no indictment, that sounds like an ever-more-desperate smear campaign.

So I guess in my own way I too am done with politics-as-usual and angry at the establishment. There isn't any other person in the United States who's been more targeted by the establishment over and over again than Hilary Clinton. The more successful she is, the more specious the arguments against her become.

At this rate, I'm probably going to vote for her.

The Day Marriage Equality Became the Law of the Land

On February 14th, 2004, thousands of couples were lining up to get married at City Hall in San Francisco. In a strange quirk of fate, we found ourselves in a great crowd of people - we accidentally chose to get married the same weekend that the city began to suddenly issue marriage licenses to same-sex couples! After some initial confusion about where to line up and how to get the papers we needed in the pandemonium, the historic nature of the events gradually dawned on me. Like being an immigrant for the first time, sometimes it takes a jolt of someone else's reality to see the basic wrongness in classifying people as "normal" and "other". And of course I grew up in Yorkshire, not San Francisco, so a lot was still new to me. It gave me a lot to ponder for several days, and among other things I wrote and we recorded this song.

Six months to the day later, on August 14th, we were back in San Francisco. We'd moved to Pittsburgh, Pennsylvania, but we got a slot for a green-card interview back in San Francisco, and so back we went. While we were there, the court ruling came through that the marriages from that day six months earlier were null-and-void. Luckily again for us, the headlines were one bit overblown - it wasn't all marriages from that day, the court was, ahem, discriminating enough to let the handful of straight marriages stand. It was unfair and depressing, and all too aware of the situation, we had a lot of survivor's guilt.

In a surprise turn, Maryl and I found ourselves invited to speak and even sing in front of a rally that evening, in front of the same City Hall where we were married. We were introduced, not surprisingly, as "a couple whose marriage would stand", and understandably when they saw us, most of the crowd were probably as surprised as we were. I remember, we talked of the privilege of marriage, how as an international couple it was crucial to our being able to stay together, and how irrational it was to make immigration and any number of other legal decisions based on your partner's gender. We said it was wrong, and that we would do our best to help put it right, which people appreciated.

Then what I remember saying was something like the following:

"Our culture does not protect freedom by restricting freedom. We don't protect democracy by saying that only males can vote. We don't protect liberty by saying that only white people can be free. We don't protect the Bible by saying you can only read it in Latin." (A few chuckles.)

"And we don't protect marriage by saying that only straight couples can marry!" (Reverberating cheers.)

"Today we're still together, still married. But for the sake of freedom to love each other, our marriage will not be fully complete, will not be fully consecrated, until everyone shares that freedom." And then we sang the song, and people started to join in the chorus, "Those who love has joined together ever will united be."

And it came to fulfillment today, June 26th 2015. The Supreme Court of the United States issued a ruling saying that barring same-sex couples from being legally married is in conflict with the Fourteenth Amendment to the Constitution, which includes "No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States".

It has come true, we have come so far together, cherishing the love we had then and seeing it grow so much already. My heart goes out to the whole nation, especially to those whose rights are sundered no longer. May those who are hurting find peace in their hearts across the country. May we all find freedom from the very idea that freedoms for one group must be taken from another. But selfishly, my heart is at home tonight. For some of the years in between, we thought we'd glimpsed something that was right, that was coming, but that was not to be for decades. We were wrong. Tonight I'm happy as well for us, for our freedom to marry, that was once restricted, is consecrated today.

Round the World

The Earth is roughly spherical in shape, as everyone reading this knows. What's often more of a surprise is that this part of core science has been known to humans for some millennia, and has remained generally accepted and largely uncontroversial. We see mountaintops in the distance before we see the plains below, and we see that masthead of an approaching ship before we see the hull. We see the shadow of the Earth upon the face of the moon during a lunar eclipse, and it is always circular. At different latitudes, we see different stars at night, and the sun casts shadows of different lengths during the day. These pieces of evidence are all documented in ancient times, and were gathered together in Aristotle's treatise On the Heavens (Book II, Ch 14), which means they were all known by around 350BC at the latest. This led to the prediction that you could travel in a particular direction and eventually return to the place from which you started, a hypothesis that was confirmed by the Magellan expedition nearly 2000 years later.

The practical importance of this discovery appears in many engineering situations. It's often necessary for planning and executing journeys of more than a few hundred miles. It's vital for understanding weather patterns. It's vital for long-distance communication: once the railway and the telegraph were standard, it became apparent quite quickly that some system of coordinated time and corresponding time zones was necessary to synchronize watches around the planet. Software engineers dealing with any kind of geographic application learn very quickly that trying to treat latitudes and longitudes as Cartesian coordinates is asking for trouble: and if we go back into the history of mathematics, we find that this is just what sines and cosines were invented for.

In about 180 BC, Eratosthenes of Alexandria used the difference in lengths of shadows at midday at different latitudes to estimate the circumference of the Earth, and this gave a much more accurate figure than the estimate used by Christopher Columbus to convince Queen Isabella that the east coast of China was within reach of a well-provisioned sea voyage. Like many children in school, I read that Columbus was one of the first people to believe that the Earth was round. Not true: instead, he was the first to place enough faith in an optimistically small estimate of the Earth's circumference that he was willing to risk a westward voyage from Europe to China. In the event, his ignorance of geography was turned into good fortune thanks only to the intervention of an unexpected continent in between.

In between the mathematicians of the ancient world and the European renaissance lies the period of the Middle Ages. Readers of many standard histories may be left with the impression that in this period at least, Europeans in particular believed that the Earth was flat. This is generally false: the overwhelming majority of writers who touched on the subject assumed that the reader knows that the Earth is round. These include Augustine, Bede, Aquinas, over 70 other medieval churchmen, and of course a whole range of Arab, Indian and Chinese scholars and sailors. From around 1000AD, the knowledge assumed increasing practical importance as the mariner's compass and sailing into the wind made regular longer voyages possible, particularly over the Indian Ocean. The European renaissance and voyages of discovery did not come from nowhere, but from centuries of gradual technological advances during which common knowledge of the shape of the Earth played a central part. By the time Copernicus was able to write his pivotal work On the Revolutions of the Heavenly Spheres, he could state firmly in his second paragraph that the Earth is spherical, give a short list of demonstrations similar to those above, and know that every educated reader would agree with his book thus far.

Given the importance of the Earth's shape in the day to day life of many professions, why is the story of this knowledge relatively obscure compared to that of the Earth's movement in the solar system? Most educated people today can give a reasonable estimate of when it became known that the Earth goes round the sun: many will say Copernicus; others will guess at Galileo which is roughly accurate to within a century. By contrast, if asked "At around what date did we know that the Earth was round?" many educated people will admit to not knowing at all, or will guess at a similar time in the early modern period.

In the rest of this brief essay, I will propose three reasons for this absence: one scientific, one literary, and one religious.

The scientific reason is that the Earth's daily rotation is intimately linked to its shape, but was demonstrated much later. Ptolemy of Alexandria (who knew of course that the Earth was round) considered but dismissed the idea that the sunrise and sunset were due to the Earth itself rotating, because the surface of the Earth would have to be moving so fast that there would be enormous windstorms everywhere. This is the claim that Copernicus challenges first, before going on to discuss the movement of planets and the Earth around the Sun. Copernicus argues a kind of least-action principle – if the Earth rotating once a day is "too fast to believe", then how much harder is it to believe instead that the sphere of the immeasurably distant stars rotates once a day? To explain the lack of permanent hurricanes, Copernicus suggests that even though gases are attracted to the Earth's surface less strongly than liquids and solids, still they are attracted and pulled round as the Earth itself spins. He even goes so far as to suggest that the moon and sun may similarly attract the things near to them: to explain the lack of perpetual hurricanes, Copernicus even anticipates the law of universal gravitation! So Copernicus did contribute crucially to our knowledge of the Earth's circular motion, and the history of this discovery can understandably be confused with the history of our knowledge of the Earth's circular shape.

The literary reason is that the story of the Earth's shape lacks drama. It's like trying to write a love story about a couple who stays happily married for decades – it's dull! There is no hero thrown in jail, no individual of brilliant insight rejected by an ignorant public or a corrupt establishment, no centuries of darkness redeemed by a final enlightenment. Even worse, there's nothing that makes us today feel superior to people at other times and places with whom we feel no intellectual kinship. It doesn't fit with the narrative of modernity: instead of a revolution in thought that throws out everything that went before, it is an example of continuity, in which ancient and medieval science built a platform upon which modern science was built. If it's a dull story that doesn't fit with the standard narrative, much better to ignore it than to dwell on it. Or romanticize it: any sensible movie-maker would probably prefer the popular myth of Columbus as a steadfast and unique believer in a new idea, rather than an opportunist adventurer who got lucky in spite of using some very bad data.

The third and most controversial reason is to do with religion. During the 19^th century, books like John William Draper's History of the Conflict between Religion and Science and Andrew Dickson White's History of the Warfare of Science with Theology in Christendom dwelt considerably on a few medieval authors, particularly Cosmas of Alexandria who taught of a flat earth in a 6^th century work called Christian Topography. Though we know today that such flat-Earth believers were the exception rather than the rule, this mistake about the middle-ages spread into the 20^th century and is still with us (see the Wikipedia article on the Flat Earth Myth). The Flat Earth Myth seems to me like an unfortunate and very human accident – Cosmas' choice of title suggests that he wanted to promote his views as decidedly Christian, and later antitheist critics have been more than happy to agree with him on this score. The story reminds us that we're prone to believe things that fit with our pre-existing biases, and that fact-checking assertions about what most scholars did or not did believe in a time as distant as the middle-ages is difficult.

Science offers two important and readily accessible methods for avoiding such errors. The first is to read primary sources. For example, to find out if Copernicus could assume that the Earth was round, and what other prior knowledge could be safely assumed, who better to read than Copernicus himself? In his first and most revolutionary chapter, parts of which were mentioned above, Copernicus cites the Pythagoreans, Plato, Aristotle, Ptolemy, Plutarch, Averroes, Martianus Capella's medieval encyclopedia, and Psalm 92:4, to name but a few. Even in the cases where he proposes different explanations (for example, Ptolemy on the movement of the Earth and Averroes on that of Mercury), he assumes that their observations were correct. His "prior art" quote for the relativity of motion comes from Virgil's Aeneid, and that for the sun lighting all things comes from Sophocles' Electra. So much for the irrelevance of a liberal arts education! His demonstrations emphasize continuity with the past wherever possible, partly because he wants his theory to have the best possible chance of being accepted by his contemporaries. You might hear a scientist today claim that the scientific revolution threw out everything that came before: this has become standard in the retelling, and deriding distant people is always easier than taking the time to understand them. But for many of the pivotal minds who made that revolution, their debt to the past was gratefully and humbly acknowledged.

The second, and most important method, is to observe the world. Take the time to convince yourself that the Earth is round – don't take someone else's word for it. Take a pair of binoculars to the top of a hill and watch the ships at sea. Note the date of the next lunar eclipse (there's one coming up on April 4^th 2015, mainly visible over the Pacific regions) and look at the Earth's shadow (and first, look at the way the full moon is opposite to the sun in the sky and convince yourself that what you're seeing is the Earth's shadow!). If you travel to a distant place at a different latitude, look for a familiar constellation like Orion and see that it is higher or lower in the sky at the same time of night. These are the things that can make us fall in love with the system of the world: these are the things that make us scientists. And if you see them, remember with pride that for thousands of years, people have seen the same things with their own eyes, and in so doing, have seen beyond themselves.

Should anyone be offended by "objective truths"?

The following quote has recently been circulating:

"Imagine a world in which we are all enlightened by objective truths rather than offended by them." (Neil deGrasse Tyson, quoted from here.)

It sounds good and rational and noble for a moment, but only for a moment: objective truth alone is not a sufficient motivation for making a statement. As parents, of course, we've had this discussion with our children many times.

"Look, that girl's bigger than me and she still has to ride with training wheels!" 

"Don't shout that across the playground, sweetie, you might make her feel bad and then she might give up and not improve. It's also boasting about being better than other people and that makes you sound unkind, which isn't fair to yourself." 

"But it's true, she is bigger than me!" 

"Of course. But there are some things that are true that we don't say, because they are unkind, and saying unkind things can hurt other people and ourselves." 

And so it begins, and continues as we develop and mature. Outward appearances are an obvious place to start: if someone has a physically obvious blemish or disability, you don't remark upon it when you're introduced. If someone's giving a presentation and you see a spelling or grammatical error in their slides, you don't interrupt just to point it out. If someone farts in a meeting, you don't point across the table and say "he just farted".

Why not? Why do we have to abide by all these sensitivities? It's because communication is about much more than conveying facts. Communication has a host of complex purposes in developing and maintaining social relationships. In an increasingly complex society, we depend on these relationships and must nurture them carefully. If it is necessary for some even more pressing purpose, we may present some unpleasant-but-true statements that risk upsetting people, but this is not something we should do lightly.

Gradually we learn a range of more subtle and intangible sensitivities. When we learn someone's racial or national background, we don't list facts about how those people have been oppressors or oppressed at various times. There are several words related to sexuality and race that we are told not to use at all, even in the objectively true statement "People like you used to be called such-and-such". If some such observation is a relevant and important contribution to an ongoing conversation (for example, in a discussion about the language used by authors from other periods), we try our best to find a polite and sensitive way to proceed.

More subtle still are statements that are true but distort the truth. For example, most people can't program computers. No problem so far, most people haven't learned. It pretty much follows that most men can't program computers, and that most women can't program computers. Now, suppose I start a conversation with "Most women can't program computers". Being true doesn't make this statement good - the fact that it's true makes its use to promote a groundless sexist judgement even worse.

I'm guessing - at least, I hope - that if the reader has made it this far that we're in broad agreement. "It's true" is not normally considered a good excuse for deliberately upsetting people.

Sadly, these norms are sometimes ignored when we discuss politics or religion. As a case-in-point, consider a popular scientist's messages on Christmas Day (quoted above), saying that it is Isaac Newton's birthday (which it is), in the USA it is a "shopping holiday" (somewhat true, but a partial distortion), and that people should be enlightened not upset because this is objective truth. Much of the rest is predictable: people vilify one another, some Christians end up with a worse impression of science than before, and those who dislike Christianity say the whole thing is the fault of Christians because obviously Christians can't think rationally.

If you don't see anything wrong here, consider similar actions with a different target. For example, we celebrate Passover at home. Public figures never intrude by publishing messages saying that in the USA it's an "eating holiday". If they did, there would be an outcry: not because the statement is false, not because it causes material harm to people, but because it's going out of ones way to insult Jewish families.

If you change the nouns used in an argument and no longer agree with the conclusion, then the argument is a fallacy. That is the very bedrock of logic. So if you think such a statement made to Christian families is jolly good fun, but made to Jewish families would be reprehensible, you must question your motivation.

This behavior is bad for at least two reasons. First, it's a bit cruel. As the messages were published, millions of American Christians were celebrating with their families, staying home, and bothering nobody else on this particular day. If they're not hurting anyone, a cheap put-down brings but a moment of glee, paid for by a lasting increase in resentment. That's a bad deal for everyone. Secondly, it fuels a contemporary presumption that scientists and other rational people should not be religious. With this comes some nasty put-downs, which are a disgrace to the legacy of great scientists such as Copernicus, Newton and Einstein, who were not only deeply religious, but are also remembered as showing great compassion for others.

We need to promote the use of science to guide the survival of life on our planet through the coming centuries: to honor the great scientists of the past, there can be no more fitting and no more pressing tribute. For this to work, we all have to find common ground and work together. If scientists use their position to insult large groups of people, are they striving for a good outcome for everyone, or like so many politicians, are they satisfied with a bad outcome so long as they can blame it on "the other side"? If you want religious people to hear the word of science as clearly as they hear the word of God, stop putting them down.

If we truly revere Sir Isaac Newton (as well we should), let us follow some guidance from one of his many tracts in his lifelong quest for true religion:

"We must love our neighbour as our selves, we must be charitable to all men for charity is the greatest of graces, greater than even faith or hope & covers a multitude of sins."