The streets

were filled with starving beggars and littered with the bodies of the dead or dying.
Shocked to the bone by what he saw, he spent days alone (five days beneath the Bodhi tree), attempting to come to terms with this shattering revelation. He found himself unable to accept his experiences as reality, and from there came he formed the basis of his teachings, that human existence is an illusion, and nothing is real. He left the palace and travelled widely, teaching.