Does the Buddha still exist after death?
One of the questions that the Buddha of the Pali canon says is not worth pursuing was whether the Buddha still exists after the death of his physical body. This question was said to be among those items of curiosity that were not edifying; nothing hinges on the answer to the question, so there is no possible advantage involved in knowing the answer.
That the Buddha discouraged people from asking the question, however, did not prevent Buddhists from asking it and trying to provide answers. Since there are really only two possible answers to that question, it is not surprising that there were some Buddhists who answered it one way and some who answered it in the opposite way. For those who gave a positive answer, the view was that the Buddha’s mind continues forever more to enjoy the bliss associated with liberation from greed, hatred and delusion. For those who gave a negative answer, the view was that since greed, hatred and delusion are the causes of being reborn, when greed, hatred and delusion are eliminated, there is nothing to cause the mind to continue into another life. So for these Buddhists, when one who has attained nirvāṇa dies, that is the end of the story. There would be no point in continuing to exist in a state of bliss.
This concludes the discussion of the Buddha as found in the Pali canon of Theravāda Buddhism. In the forms of Buddhism that accepted texts outside the early canonical literature, attention was focussed on many more Buddhas than the so-called historical Buddha, Siddhārtha Gautama. This naturally raised the question of how all these Buddhas related to one another. Specifically, the question arose: Are there many Buddhas or just one?