John Collins was Bobby Fischer's coach in Brooklyn when Bobby was young. Another of John's famous students was IM Donald Byrne. Professor Byrne was Dan's coach when Dan was in college. Every adult should consider having a mental hobby.
Studies continually show they help the brain, especially as one ages.
So if not chess, take up backgammon, bridge, crossword puzzle solving, cryptograms, or something. Lots of older people jog or play golf or tennis. They also need a mental hobby to keep their brain active. Current and former students are invited to attend my annual pizza party , held at the World Open every year. These differ completely from the Private Lessons that Dan gives at his house.