• excerpted from a talk by Alan Kay at TED

As a former molecular biologist, I don't like most simulations of the inside of the cell at all. Not because they aren't beautiful or anything, but because they miss the thing that most students fail to understand about molecular biology: why is there any probability at all of two complex shapes finding each other just the right way so that they can combine together and be catalyzed?

What you see is every reaction being fortuitous; the molecules just swoop in the air and bind, and something happens. But in fact those molecules are spinning at the rate of about a million revolutions per second. They're agitating back and forth their size every two nanoseconds. They're completely crowded together. They're jammed, they're bashing up against each other.

And if you don't understand that in your mental model of this stuff, what happens inside of a cell seems completely mysterious and fortuitous. And I think that's exactly the wrong image for when you're trying to teach science.