Four sights

According to accounts of Gautama Buddha's life, he led a sheltered existence as a prince surrounded by luxury and pleasure in his younger years.

One day he violated the king's orders by sneaking out for an unannounced excursion outside the royal palace. There he saw the four sights that were his inspiration to become a monk: an old crippled man (old age), a diseased man (illness), a decaying corpse (death), and finally an ascetic.