Comment by dkarl

Mine was opposite in a different direction. My dad was a historian. When I was seven or eight, we had an outdoor cat (didn't get along with the indoor cats) and needed a table to keep its food dish off the ground. The cat's name was Tiny, and it weighed about eight pounds. My dad spent an afternoon hammering the table together out of board scraps, and it shook and sagged when Tiny jumped on it. I (the budding math nerd) was babbling to him the whole afternoon about how he needed triangles because parallelograms can change their shape without changing the length of their sides. It didn't make any sense to him so he ignored me until his table went catawampus trying to hold up half its weight. Then he added some triangles where I told him to. I don't remember him ever building anything again, except we rebuilt our backyard fence exactly the way it had been built fifteen years earlier by someone else. By that time I was in college, and we worked better together.