Where things are and what they look like
How many holes does a straw have?
Giving the same name to different things
"His style was invincibility"
The mysterious power of trial and error
Artificial Intelligence as mountaineering
You are your own negative-first cousin, and other maps
What happened today will happen tomorrow
The terrible law of increase
How math broke democracy (and might still save it)
I prove a theorem and the house expands.