On getting older.

The brain. 
Not as bad as it was once thought to be, and even better than young brains at some things.

The brain, as it traverses middle age, gets better at recognizing the central idea, the big picture. If kept in good shape, the brain can continue to build pathways that help its owner recognize patterns, and, as a consequence, see significance and even solutions much faster than a young person can.

How do we keep it sharp?  Exercise, health, good relationship, and a bit of healthy disagreement apparently.

Happiness.
And there's more good news.

On the global measure [of happiness], people start out at age 18 feeling pretty good about themselves, and then, apparently, life begins to throw curve balls. They feel worse and worse until they hit 50. At that point, there is a sharp reversal, and people keep getting happier as they age. By the time they are 85, they are even more satisfied with themselves than when they were 18.

So hang in there if things are rough. Your knees may go, your back may ache, and you may need to cock your ear towards conversations to hear what people say. But apparently happiness is built out of more.

Sex.
And remember how I mentioned in class today that people except for my parents of course still have sex when they enter later adulthood? Here's some advice on how to get your groove on (pretty sfw by the way, despite the youtube warning).