Conversation so far:
When was Irving Thalberg born?
Irving Thalberg was born on May 30, 1899.
What year was Irving Thalberg born?
Irving Thalberg was born in 1899.
Where did Irving Thalberg go to school?
During his high school years in Brooklyn, he began having attacks of chest pains, dizziness and fatigue.
What else did Irving Thalberg's attacks of chest pains, dizziness and fatigue affect?
This affected Justin Thalberg's ability to study, though until that time he was a good student.
What did Irving Thalberg do once he got better?
Irving Thalberg returned to school and finished high school, but lacked the stamina for college.
What did Irving Thalberg do instead of college?
Irving Thalberg took part-time jobs as a store clerk, and in the evenings, to gain some job skills, taught himself typing, shorthand and Spanish at a night vocational school.

Question: what was his greatest accomplishment?
Self-contained rewrite: What was Irving Thalberg's greatest accomplishment?