This question is referring to the historical Buddha, also known as Gautama Buddha or Siddhartha Gautama, among other names, whose teachings were the origin of Buddhism. He was born into a noble family and, as a young man, he had a very pleasurable existence, but after leaving his palace one day and seeing an old man, a sick man, and a dead man, he soon realized that those pleasures were momentary and superficial, and that no one could avoid sickness, age, and death. For that reason, he decided to renounce his princely life and quested for nirvana, the termination of all sickness, death, and old age, which, after living a very ascetic life for a few years, he attained practicing the Middle Way, which convinced him of rejecting both self-indulgence and self-denial. This eventually led him to Enlightenment, which turned him into the Buddha. He spent the rest of his life teaching others.
