Conversation so far:
Where was Sam Harris born?
in Los Angeles.
What did his parents do for a living?
the son of actor Berkeley Harris and TV producer Susan Harris.
Was his family in any type of religion?
His father came from a Quaker background and his mother is a secular Jew.
Where did Sam Harris attend college?
Stanford University.
What was his major?
his original major was in English.
What did he do after he left Stanford?
He received a Ph.D.
degree in cognitive neuroscience in 2009 from the University of California, Los Angeles.
What was the name of his first book?
CANNOTANSWER.

Question: What the topic of his thesis  ?
Self-contained rewrite: What the topic of Sam Harris's thesis?