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Last Friday I bought a very simple toy: a set of 216 little magnetic metal balls, about the size of ball bearings. Since then I've been completely entranced by it and unable to put the thing down. Here's a Flickr group to show what I mean. The little balls seem to want to come together in symmetrical patterns: you can make square and hexagonal flat patches, curved patches with 3/4/5/6-fold symmetry, stable 3D cubic lattices, fcc and hcp lattices and many hollow and solid polyhedra. So far I've managed to make a tetrahedron, two varieties of cube (1, 2), an octahedron, an icosahedron, and other stuff (my current favorite shape is the solid truncated octahedron). It's like crack for the right type of person.
And there's the rub. Carrying this toy around and showing it to my friends has made me realize with forgotten clarity that I'm special. Practically no one reacts to it the same way as me. The word "aspie" has been uttered, half in jest, half seriously. Even though my intelligence may be pretty average (judging by online tests I have lower IQ than most LW regulars), I seem to have this rare natural ability to get deeply interested in things that "normal" people find boring.
This ability... this instinctive desire to tinker with symmetrical patterns... has shaped my entire life by now, because it's what first attracted me to math and then programming. But how could it ever be environmental, if I remember having it since my earliest childhood? Is it genetic? Is math success genetic, then? What do you think?
I once spent a surprisingly enlightening five minutes at an office Christmas party trying to explain "the beat" to a work colleague. This mostly involved slapping the back of a chair in time to Sisters Are Doing It For Themselves and shouting "seriously, can you not hear that?" This was a completely alien concept to me. How can someone not hear the beat in a piece of music?
Since then I've taken up a number of musical and dance-related hobbies, and it's become apparent to me that some people simply can't hear the patterns in a piece of music. They don't know what a key change is because they can't distinguish between two different keys. They can't tell when a break is coming up, even when the piece is issuing a screaming telegraph that it's about to break. To them it's just nice noise.
I've found maths to be a bit similar. When demonstrating something mathematically, there are some people who just can't see how or why one thing is isomorphic to another, or why it's self-evident that if this is the case, that must also be the case. Others without any maths training at all can spot the same thing right away, and call it a good intuitive example.
This does make me worry a bit, because I'm not aware of anything I "just can't do" in this fashion. There are plenty of things I'm bad at, but I'm at least capable of recognising the criteria by which I'm bad at them. Is there anything out there my brain simply isn't wired to perceive properly, and how can I even tell if I find it?
I used to teach Sunday school, and some of it involved having students do a little singing. I was shocked at the number of ten-year-old kids who could not sing back a pattern of pitches by ear. I'm not talking about singing beautifully, or in tune; I'm talking about distinguishing flat, rising, or falling tones. The scary part? These were kids who had taken music lessons. I still don't understand it; maybe it wasn't inability at all, just passive resistance because they didn't want to be there.