The Fool is the soul unencumbered by the trappings of the ego, mores of society, and expectations. He is a traveler, who carries no baggage
A lot of esoteric cultures believe in reincarnation. The date of birth thus is coded information on what the soul plans on accomplishing now.
Understanding Tarot Through Mythology Series: Dionysus the Greek God is a perfect personification of The Fool, who seeks new experience.