Buddha also taught that suffering is essentially caused by ignorance and our own mental confusion about the purpose life. The suffering we experience can end once we rid ourselves of this confusion through the path of personal development. Otherwise, this confusion and ignorance causes us to perform unwanted activities that become part of our karma that must be endured in this or another existence. When karma ceases, so does the need for birth and, naturally, old age, sorrow, and death. With the cessation of birth, there is the cessation of consciousness and entrance into nirvana follows. Thus, according to this, there is no soul and no personal God, but only the void, the nothingness that is the essence of everything to which we must return. Although this was the basic premise from which Buddha taught, this theory was mentioned in the Nasadiya-sukta of the Rig-veda long before Buddha ever appeared.
However, Buddha refused to discuss how the world was created or what was existence in nirvana. He simply taught that one should live in a way that would produce no more karma while enduring whatever karmic reactions destiny brought. This would free one from further rebirth.