Irregular Webcomic! #3765

Last week (as I type this) I did another one of my Scientists in Schools visits, visiting a local school to talk to the kids about science stuff. This time, instead of me preparing a presentation on a specific topic, I arranged with the school's science coordinator to do a general Q&A session with each group of students. Most of the classes had done some preparation the week before, their teachers organising to get questions the kids wanted answered, and writing them down on paper so the kids would remember them on the day.

The kindergarten class didn't do this. They just came in and all put their hands up when I said, "who's got a question?" The first child asked "How many animals are there in the world?" Not knowing the answer to this offhand, I explained briefly how a scientist would go about finding the answer (by doing small surveys of areas and extrapolating up from there to get a rough idea - only in words kindergarten kids would understand). I concluded by saying there are probably "billions and billions" of animals - doing my best to channel Carl Sagan.

Next question. "How many giraffes are there?"

I reiterated how you could find out, and said they were big animals and only lived in a small part of Africa, so not that many, probably less than a million.^[1]

Next question: "How many turtles are there?"

At this point a teacher stepped in and said, "No more 'how many' questions... Who's got a different question?" This only headed things off for one question (I forget what it was), and then the next question after that was "How many rocks are there?" And then the next question was "How many bones are there?" I asked to clarify, "You mean how many bones in our bodies?" "No, how many bones in the world?"

In short, kindergarten kids can have a one-track mind sometimes. Anyway, questions with the older classes went much more smoothly.

The year 5 and 6 kids, however, showed a distinct existential bent. The opening question was "How do you make a bomb?" I explained to the best of my ability how chemical explosives work, but then said that it was chemistry and I studied physics, so I know more about how to make a nuclear bomb, then proceeded to explain to them how you make a nuclear bomb. I said to them, "Now you can go home tonight and tell your parents that today at school you learnt how to make a nuclear bomb," which elicited a good laugh from everyone. I also said I didn't mind telling them how to make a nuclear bomb, because you need plutonium to do it, and there's no way they could get their hands on plutonium.

The next question was, "Is reincarnation real?" I used this as an opening to talk about the scientific method, and how scientists work, gathering evidence and doing experiments.

"Can you think of any experiment you can do to test whether reincarnation is real? (lots of kids shaking their heads no) Well, you might kill someone and see if they come back in another life... but that's not a very good experiment and most people would say that's a really bad thing to do. Maybe you could interview people and see how many of them say that they had lived in a previous life. But then you have to decide how much you can trust those people." And so on.

Another question: "Will the Earth ever be destroyed?" I explained how our sun will expand into a red giant in about 4 billion years, destroying all life on Earth. But hopefully by then we'll have colonised planets around other stars.

"Will a meteor destroy human civilisation, like it did the dinosaurs?"

And then: "What happens when we die?" Clearly kids of about this age have recently discovered their own mortality, and they find it a strange or frightening concept.

For the record, I said that as far as science goes, when you die and your brain activity stops, that is the end of your consciousness. "It probably won't feel like anything, the same as when you're in a deep, dreamless sleep. Or before you were born - do any of you remember what it felt like 50 or 100 years ago before you were born? (head shakes all around) There's no pain or fear, being dead will feel the same as that." This seemed to assuage the obvious fears of some of the kids, as I could see looks of relief on several of them. "That's as far as science and evidence goes. We can't talk to dead people, so we don't know for sure if their consciousness is just gone, or if it continues in any way. Various religions have different ideas about what happens, reincarnation like we were talking about before is one of those ideas. Heaven is another one. Different people believe different things, and science doesn't always have all the answers."

It's certainly an interesting experience, talking to kids about stuff like this, being frank about how science works, while at the same time trying not to scare them or disrespect any religious beliefs they've been exposed to and are trying to sort out as they grow up.

[1] As it turns out, there are about 100,000 individual giraffes in the world.