I believe this image is from his book The Science of Hitting.
Williams has a fairly fascinating biography and I'd encourage people to browse his story a bit. A few interesting things about him:
- He served in both World War II and the Korean War. During the latter, he crash landed his plane after it took heavy fire.
- He was an amazing angler and at times held tarpon or bonefish records. I believe he's also in the fishing hall of fame.
- He was actually a terrible baseball manager. Most people attribute this to giving no attention to pitchers and not being able to handle that his players simply weren't as gifted or as disciplined as him.
- He was the last player to have a batting average > .400 for a full season [1] but amazingly did not win the Most Valuable Player award that year. It went to Joe DiMaggio.
[1] For those who don't follow baseball, this is calculated as (hits / at bats) and generally the modern-day leaders vary between .330 and .375 (see https://www.baseball-reference.com/leaders/batting_avg_top_t...).