October 4:
(1) (1890) American physician and radiologist Alan L. Hart was born. He is known for helping to implement tuberculosis screening programs, saving thousands of lives.
(2) (1904) American physicist and inventor John Vincent Atanasoff was born. He is known for inventing the first electronic digital computer.
(3) (1929) American psychiatrist and writer John E. Mack was born. His early research focused on mental health, and later he focused his research on the spiritual changes people undergo after alien abduction experiences.