How well do you understand the physical world?
Some time ago, I realized that I had never really wondered about the physical causes of many little things that were happening around me. We all live in a physical universe, and yet most of us take its operations for granted. We may have the comfortable conviction that there’s a scientific explanation for everything we see, and so we may consider ourselves rationalists. But if we don’t ourselves know the explanations for many of the events of our daily lives, then practically speaking it’s like we are surrounded by magic and mystery.
Over the years, I’ve assembled a list of some strikingly common and obvious phenomena whose causes most people don’t actually know—not because they’re unable to understand, because the explanations are usually not so very complex, but merely because they’ve never bothered to ask.
Here are a dozen of my favorites. How many of them can you yourself explain? I used to make the mistake of cheerfully confronting friends and acquaintances with these questions, but I stopped because I found it usually annoyed the hell out of them. Even though my point was that I had myself spent most of my life blissfully ignorant of the explanations for some of these phenomena, bringing them up in conversation inevitably gave me a know-it-all air, I think. Hopefully blogging about them won’t have the same effect.
1) Why is the sky blue (and why do clouds look red and yellow at sunset)?
2) Why does the sun emit light?
3) Why do things look black and white in moonlight?
4) Why does water put out fires?
5) Why do wool and down keep you so warm?
6) Why is it colder in winter and warmer in summer?
7) Why does lightning produce the sound we call thunder?
8) Why do sharp knives cut better than dull ones?
9) Why does a magnifying glass make things look bigger?
10) What causes rainbows?
11) Why can’t you see through milk but you can see through water and vegetable oil?
12) Why does really hot water make glass crack (and why doesn’t Pyrex crack)?
© Joel Benington, 2011.
Pro-Human Extremist 
Man, you need some serious education uprades!
Robert
December 5, 2011 at 2:28 am
Funny! So should I read that as a boast that you can answer all of them without half thinking about it? If so, you may not realize that you’re in a small minority even of educated people. Only about one in ten people I’ve asked know off the top of their head why sharp knives cut better, though most (like you?) have thought the question is trivially easy when first asked about it–and most of the people I’ve confronted with the question have advanced degrees. They all need education upgrades in your opinion?
Joel Benington
December 5, 2011 at 3:02 am
Apparently you don’t have much to teach and your students are likely just going through the motions of getting a piece of paper, not truly interrested in learning? I’d do the same!
Cheers
Robert
December 5, 2011 at 3:09 am
I can answer all of them better than you apparently. It never stops amazing me how some people can go through life incapable of deling with reality in any meaningful way, and you seem to be telling me you can’t. Incapaple of ultimately preserving their own physical survival?
Robert
December 5, 2011 at 3:05 am
And yet a degree hasn’t imparted intelligence to you or your colleagues apart from mastering the system to an extent. Drones!
Robert
December 5, 2011 at 3:17 am
Ah, now I see–you’re just ranting for fun, right? Well, knock yourself out if you’ve nothing better to do.
Joel Benington
December 5, 2011 at 3:21 am
OK partner, you go sharpen that mental knife of yours and have a good week.
Robert
December 5, 2011 at 3:28 am
I think it’s worth pointing out that it sounds profoundly uneducated to insist that someone who is so educated is, in fact, uneducated. Likewise, it sounds profoundly unprofessional to assert that a professional is, in fact, unprofessional. Furthermore, it sounds profoundly ignorant and insincere to assume that his students are ignorant and insincere. I would tie this together by suggesting that these assertions are actually self-illuminating on the part of the one making the assertions, but that would just be rude.
Anon Follower
December 5, 2011 at 4:28 pm
I 100% agree, which is why I would never call someone uneducated or unprofessional or ignorant or insincere—especially not for something as trivial as not knowing why water puts out fires. I’m very sorry to have given you that impression, and I’d be most grateful if you could point out what specifically I said that led you to that conclusion.
I really did try my hardest to stress that I hadn’t begun to wonder about many of these things until comparatively recently, so I certainly wouldn’t judge others for not having wondered about them. For example, I had given no real thought to why sharp knives cut better or why water puts out fires until I was considerably older than my students are now. I’ve understood blue skies and rainbows for somewhat longer, but again I think I first came across explanations of those phenomena after college (I didn’t major in the sciences). So any of my students who already understand them would be ahead of where I was at their age!
Joel Benington
December 5, 2011 at 7:24 pm
I meant that as a response to Robert’s comments, not your post!
Anon Follower
December 6, 2011 at 1:26 am
Yes–I see that now. Sorry for having misunderstood you. I’ve been so busy preparing for exams that I didn’t read carefully enough. But look what you did with your response–you woke the sleeping beast! 🙂
Joel Benington
December 7, 2011 at 1:24 am
There was a time when so called educated men knew about general things in life, it gave them credibility. If you can’t change a flat tire, then my consolatiosn to you, but are you an educator in the real siense a leader. No wonder the world is comming aprt at the seams! And you don’t know my background, I graduated within the top 3% at U of T, and that was by being a drone, only I am better than you because I knew what I was doing and the reasons for it! Einstein and me, neither one were drones.
Robert
December 6, 2011 at 1:42 am
You might have well and easily been a Nazi or a clergyman persecuting Gilileo, and you can blame it on the academic system1 Don’t you see it?
Robert
December 6, 2011 at 1:48 am
Your stupidity is systemic! Blame it on everyone else after it all washes out, you were after, all only part of the system. You aren’t a leader as a teacher translates into greek, you are the least of all a leader, and that goes way above you to the very top of the system.
Robert
December 6, 2011 at 2:01 am
Some clown with academic credentials from chicago says to let business regulate itself. Eventually this is a realized policy of error in the american government itself that is threatening the collapse of the entire world eonomy.He was a teacher, not at all unlike you! I pay taxes, let me regulate myself?
Robert
December 6, 2011 at 2:10 am
The american government with o-bumma is is currently not any smarter than the self-serving bush and cares not about the fact it’s paradigms are wrong!
Robert
December 6, 2011 at 2:12 am
And you can’t change a flat tire! Your a teacher and you couldn’t change anything at all?
Robert
December 6, 2011 at 2:27 am
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