All the efforts of the human mind cannot exhaust the essence of a single fly.
Actually, not born, but celebrated, no?
Well, it is certainly his feast day. But those are usually on the the date of a saint's death (birth into eternity). But Thomas died on March 7, 1274. I don't know if we actually know his birth date. But the Wikipedia entry for births on this date has today as his birthday, and I ran with that.