1. There is a conservation principle for laughter.  If I say something funny and sit stone-faced, you will laugh.  If I laugh, you probably won’t.  People in a room can be ranked by their laughter valence.  Any given joke gets a certain quantity of laughs and these come from those with the lowest valence.  Sandeep’s valence is minus infinity. This ignores social laughter where I laugh not because the joke is funny but just because everyone else is laughing.
  2. Women should be attracted to older men because survival to old age indicates good genes.  The effect is weaker in the other direction (men being attracted to older women) because the opportunity cost of another mate is zero for men.  This explains why men “age gracefully.”
  3. Skilled interrogators presumably are trained to understand and leverage the curse of knowledge:  the fact that you know something makes it very difficult to imitate the frame of mind you would have if you did not know it.
  4. The things gay men do to make themselves attractive to other men also makes them attractive to women.  Not so for lesbians vis a vis men.  I am not sure I have a good theory for this one.