https://www.dalailama.com/the-dalai-lama/biography-and-daily-life/reincarnation
The Dalai Lamas have functioned as both the political and spiritual leaders of Tibet for 369 years since 1642. I have now voluntarily brought this to an end, proud and satisfied that we can pursue the kind of democratic system of government flourishing elsewhere in the world. In fact, as far back as 1969, I made clear that concerned people should decide whether the Dalai Lama’s reincarnations should continue in the future. However, in the absence of clear guidelines, should the concerned public express a strong wish for the Dalai Lamas to continue, there is an obvious risk of vested political interests misusing the reincarnation system to fulfil their own political agenda. Therefore, while I remain physically and mentally fit, it seems important to me that we draw up clear guidelines to recognise the next Dalai Lama, so that there is no room for doubt or deception. For these guidelines to be fully comprehensible, it is essential to understand the system of Tulku recognition and the basic concepts behind it. Therefore, I shall briefly explain them below.
Past and future lives
In order to accept reincarnation or the reality of Tulkus, we need to accept the existence of past and future lives. Sentient beings come to this present life from their previous lives and take rebirth again after death. This kind of continuous rebirth is accepted by all the ancient Indian spiritual traditions and schools of philosophy, except the Charvakas, who were a materialist movement. Some modern thinkers deny past and future lives on the premise that we cannot see them. Others do not draw such clear cut conclusions on this basis.
Although many religious traditions accept rebirth, they differ in their views of what it is that is reborn, how it is reborn, and how it passes through the transitional period between two lives. Some religious traditions accept the prospect of future life, but reject the idea of past lives.
Generally, Buddhists believe that there is no beginning to birth and that once we achieve liberation from the cycle of existence by overcoming our karma and destructive emotions, we will not be reborn under the sway of these conditions. Therefore, Buddhists believe that there is an end to being reborn as a result of karma and destructive emotions, but most Buddhist philosophical schools do not accept that the mind-stream comes to an end. To reject past and future rebirth would contradict the Buddhist concept of the ground, path and result, which must be explained on the basis of the disciplined or undisciplined mind. If we accept this argument, logically, we would also have to accept that the world and its inhabitants come about without causes and conditions. Therefore, as long as you are a Buddhist, it is necessary to accept past and future rebirth.
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