My commonsense position on intelligent extraterrestial life: it surely exists, but very likely its lightcone and our lightcone don’t intersect, so we can’t interact with it because it’s too far away, too long ago or too far in the future. In this way aliens are like God: the universe in which they exist isn’t necessarily observationally distinct from the one in which they don’t.

A couple of days ago, the ACLU (American Civil Liberties Union) tweeted “This is the future that ACLU members want” with a picture of a toddler with a shirt saying “Free Speech” and holding a US flag. Responses included:

• “A White kid with a flag?!”
• “What? All blond folk! I don’t get this silly post. The future ACLU wants is a little blond kid???”
• “I’d rather have this future:”, with several pictures of black characters from TV shows.

Soon, the ACLU account responded with “When your Twitter followers keep you in check and remind you that white supremacy is everywhere”, with a reaction gif of Kermit the Frog saying “That’s a very good point” – meaning that the ACLU conceded the point.

Possibly some of the commenters didn’t notice the words on the shirt, “Free Speech”, and only noticed the whiteness of the child, and made the sinister connection with “the future that ACLU members want” plus an American flag. Other comments may have not noticed the whiteness and kept looking for the point of the picture, which is the shirt. Other tweeters reacted with offense upon offense; “What has the world come to when a picture of a white kid is racist?” This must be one of the button-pushiest issues imaginable. Whose babies do we really like?

Also a couple of days ago, the chairman of the Finnish Social Democratic Party, Antti Rinne, expressed concern about low fertility numbers in Finland. He called on everyone to “pitch in” on this and make more babies, saying “Two is already well done”. Commentators were appalled, members of his own party evoked the Third Reich and his choice of words was universally condemned.

Some of the pushback was opposed to the idea of a man telling women what to do about reproduction, and some had to do with environmental concerns (“There’s already too many of us”). A lot of it was about the nation-building connotation. As a positive solution, many promoted increasing immigration instead (this included many who were concerned about the environmental impact of having children). One comment was “Finland doesn’t need more babies. Finland needs more immigrants.”

Despite the PR catastrophe, I think Rinne had some political wisdom. This issue of “our babies” vs. “those immigrants” is extremely potent, and even a ham-handed display of approval of “our babies” can be very valuable.

Of course, it’s potent in the other direction too. On the opposite side of the political spectrum, it is extremely distasteful to show preference for “us” over “them”, and many will now suspect Rinne of that. The idea itself of “us” and “them” in the context of babies is dangerous – to that side of the spectrum, which I might as well call the left, “us” and “them” applies to class and politics, not to ethnic groups.

Also a couple of days ago, there was a knife attack in the Finnish city of Turku killing two and wounding another eight. The attacker was a Moroccan asylum seeker who had been denied asylum. In the initial press conference, when solid information was scarce, the minister for the interior, Päivi Risikko, relayed the information that the attacker had been “foreign-looking”. This was met with dismay and disapproval. Does Päivi Risikko not know that there are dark-skinned Finns now? The “non-Finnish-looking” posted selfies challenging anyone to say what a Finnish person looks like. Parents of dark-skinned children took to Facebook to voice their concern that their children will be stigmatised as “non-Finnish-looking”. Columnists made the point, obvious to them, that there is no such thing as “Finnish-looking”. That perhaps there never was, but there certainly isn’t now.

Of course, this whole thing only made it obvious to everyone that it is pretty clear what “Finnish-looking” means. If it didn’t mean anything, there would be nothing to talk about. Predicting who might have felt their “Finnish-lookingness” questioned would not have been difficult.

(In case you’re wondering, I am sometimes asked about my non-Finnish name. It has not occurred to me to respond that there is nothing non-Finnish about my name, because these days Finns are named all kinds of things.)

That there is no such thing as “Finnish-looking” is something that educated Finns might be able to believe, but certainly Middle-Eastern and African immigrants, such as the attacker, who might be among a “Finnish-looking” majority for the first time in their lives, know exactly what it means. Those of a truly impeccable moral character might feel that there is no “us” and “them” between ethnic Finns and recent far-group immigrants, but hardly any of those immigrants fail to consider their own co-ethnics an ingroup. It is an iron law of social behaviour if there ever was one – people are groupish, and every emigrant group to anywhere ever has demonstrated intragroup solidarity.

Even though there is obviously every other kind of groupishness, the idea that there is no such thing as Finnishness has considerable purchase, but it is intended for domestic consumpion only. From the outside, it has the appearance of a cosmopolitan affectation. In reality, Finns are a relatively distinct ethnic and linguistic group (though not a very unified one – there is considerable distance between west and east genetically). But it is the same in every western country; of course there is no We, the very idea is both meaningless (there can be such thing) and disproved by history (did you know people have always moved around?).

As politics turns more and more to the fundamental question of politics, “Whose side are you on?”, you can expect to see more and more stake-claiming, and more talk about babies and immigrants. It did not occur to Antti Rinne to single out for praise residents of African and Middle-Eastern background, who have chidren at almost three times the rate of the rest of the population. As a demographic group, parents, who after all can hardly be politically discounted, would have reacted quite differently to that.

One of the most conspicuous areas of ignorance is genetics and heredity, particularly with reference to humans. There’s sort of a blind spot about it, where people just don’t put much thought into it and attribute a lot to randomness. For example, I have more than once had to explain why it’s obvious that Michael Jackson’s children aren’t his biological children (they don’t look half-black). Here’s some concepts that have helped me make sense of things.

Firstly, regression to the mean. This is something that happens with polygenic (lots of different alleles have an effect) traits, where the particular combination of recessive and dominant alleles matter.

For example, you might expect that when two tall people have children, the children get “tallness” genes from both of them, and as a result the children are super-tall. But that’s not what happens. The children on average will be shorter than the average of the parents. That’s because each child gets a random selection of alleles from each parent, who happen to have a combination leading to tallness, and on average the children will have a more… average combination. Their height is predicted to be between the average of the whole population and the average of the parents. Likewise, children of short parents are expected to be somewhat taller.

This leads to interesting family patterns, like intelligent parents often having less intelligent children (than themselves), and dim parents often having smarter children. How many stories could be summarized as “child disappoints parents and rebels” or “child outgrows environment and feels shame”?

Also, there’s assortative mating, meaning that similar people end up together. This causes more dim-dim couples and smart-smart couples than you’d expect by random chance. This accentuates the mismatched parent-children -effect.

The second thing is the finding that everything is heritable. I already implied that intelligence is heritable, which is something that people will dispute (along with the idea that there is such a thing as intelligence). But there is really practically nothing physical or mental about people that isn’t heritable. Not just eye color and height, but obesity and muscularity. Not just intelligence and schizophrenia risk, but sociability, professional success, areas of interest and criminality. Really, look in the literature, it’s shocking just how subtle and pervasive the effect of genes can be.

Note that the more complicated a trait is to measure, the more inaccurate the measure is, and the less we can judge heritability on an individual level. Indeed, many conclusions about heritability are too weak to worry about on the individual level but become meaningful when measuring masses of people, where random variation washes out.

The third is that heritable traits are often correlated with each other in clusters. The stories we tell children often suggest that traits are anticorrelated in the sense that “everyone is good at something”; if you’re not good at something, there’ll be something else you’re the best at. The stories we tell to adults suggest that traits are fairly uncorrelated, that you never know what you’re good at. The reality is that lots of things go together in clumps. Different kinds of intelligence predict each other – high verbal intelligence is correlated with logical reasoning ability, and both are correlated with spatial awareness. In intelligence, this general correlation factor is called “g” and is the reason for the predictive power of IQ tests (it doesn’t matter if the test isn’t perfect, because it measures all intelligence by proxy anyway).

This has led to economists half-seriously suggesting that height should be taxed, because that too is correlated with all the other positively perceived traits, especially among men.

The fourth is that heritability increases with age. Many childhood interventions to improve outcomes appear promising during childhood, become unclear in adolescence and disappear completely in adulthood. The effect of genes is constant and permanent, while the environment fluctuates. Over time, the genetic contribution comes to dominate. Also, the individual comes to select the environment for himself, compounding the effect.

It is often remarked that children become their fathers or mothers as they mature, and I think it might be that that has less to do with psychology and more with this genetic effect. I’ve also wondered whether this is partly behind the tendency of adoptees to eventually become extremely interested in knowing about their biological parents, as they become more and more different than their adoptive environment.

According to Americans, free speech in that country went from being a left-wing rallying cry in the 60’s (when leftism was countercultural, and students wanted to be able to organize politically on campus) to being a right-wing rallying cry today (when rightism is rather liberal, and people want to be able to violate speech norms about racism and equality).

In Europe, free speech has never really been a respectable rallying cry. What freedom of expression as an enlightenment value is to America, reason and tolerance are to Europe.

The process of identity liberation has clearly peaked and is in decline. We used to say a woman can be anything she wants to be, now a nonconformist woman will believe she’s non-binary, genderqueer, or a man trapped inside a woman’s body. A white person interested in another culture may be guilty of cultural colonialism or cultural appropriation, and a nonwhite person insufficiently devoted to their ethnic idenitity is whitewashing themselves or has internalized colonialism.

There are some things that people think they understand, or assume to be straightforward to understand, but are (apparently) impossible or very difficult to understand properly. I think about explaining things a lot these days due to being a dad, and I always did like explanations, but all of these stump me to some extent.

An easy one to start. Imagine that you’re standing next to a bicycle with handlebar brakes. You’re holding the bicycle up and can roll it forward or backwards. Now, imagine you engage the back wheel brake. Can you now move the bicycle backwards? What about forwards? Now, engage the front wheel brake. Can you move the bicycle backwards or forwards?

What happens is that with the back wheel brake engaged, you can move the bicycle forwards, with the front wheel rolling freely and the back wheel sliding with some friction, but not that much. But you absolutely cannot move the bicycle backwards. The front wheel will lift up, and the bicycle rests on the locked back wheel. Now, I’m not saying that I don’t understand what’s happening here. But it’s somehow awkward to put it in words, and you can easily give an explanation that is missing the point, or begging the question. Especially at a first try. Go ahead and try!

Next, how does a bicycle stay upright when you’re riding it? A lot of resources will tell you that it has to do with the gyroscopic action of the wheels spinning, but the force from that is not big enough, and besides, you can stay up even at quite low speeds. Though it does give a piece of the puzzle. In fact there’s no single explanation, just lots of little pieces. Most people can’t keep the bicycle stable without using their hands on the handlebars to provide feedback to the front wheel, but other people don’t need to do that. They rely on adjusting their centre of gravity over the bicycle, plus other effects. There isn’t really any good explanation, even if you’re an engineer. On the other hand, it’s not like the physics aren’t understood – it can be simulated in a computer just fine.

A similar case is the wing of an aeroplane. The first explanation I heard was that at the leading edge of the wing the airflow separates, some going under the wing and some over the wing. Because the trip over the wing is longer, the air gets thinner, so the pressure is lower above the wing. This low pressure then sucks the wing upwards, and that’s what causes lift. But this explanation raises many questions. Why does the air take the same amount of time going over and under the wing? Why doesn’t it get deflected and flow away? How can aeroplanes fly upside down? This is the “Bernouilli effect” explanation, and it is not sufficient, even with combined with additional effects (eg. the Coandă effect causing air to stick to the contours of the wing, like the way water flowing from a faucet will be “bended” by the side of a drinking glass put in its path).

The only thing I can really honestly say to a child about an aeroplane’s wing is that the wing pushes and sucks air down, both from above and below the wing. At least this is what smoke in wind tunnels shows. I can’t properly explain why. And that the angle at which the wing meets the air is important – only at some angles does a wing generate lift. The wing doesn’t even need to be curved, though it does help. If you fly upside down, you probably have to angle the winds differently from right-side-up flying. If you slice your hand through water in a pool you can get an idea of how the wing needs to be positioned.

And I think something like the Coandă effect does have *something* to do with it – in fact, I believe an aeroplane could not fly if air had zero viscosity, but I’m not even 100% sure about that. Again, the wing can be modeled mathematically just fine, it’s just difficult to explain in words.

Finally, a question that most people (me included) don’t even think to ask even when they easily could have – and when I first heard it, I was very confused, because I first thought I understood the elementary physics, but had in fact encountered a quantum effect. Namely, if electrons are negatively charged and protons are positively charged, why don’t the electrons fall into the nucleus? Well, isn’t it like planets and the sun, where the electrons are attracted to the nucleus but moving fast enough to keep from falling in and they stay in orbit? But an accelerating charged particle would lose energy to radiation, and when you calculate it classically, the electrons really should fall into the nucleus. Oh, I know, this is that quantum thing, where the electrons are only allowed to have certain quantized amounts of energy, so they won’t radiate anything away and just keep going around in orbit. This is the “Bohr model” of an atom, but it’s also incorrect, predicting observations only for hydrogen atoms for which it was designed.

In the end, there’s a lot you can say about the quantum nature of an atom – like that the electrons don’t have a well defined position and speed anyway, so they can never be on a trajectory falling into the nucleus, or any other point – but nothing to really satisfy our classically conditioned minds. Again the only answer is in the mathematics, but it doesn’t explain.