Rebirth
Tibetan buddhists believe in rebirth. To someone who is not a believer in any form of life after death this seems an absurdity. Which it is, if taken literally. But if speech was limited to considering only facts that are known to be true by experiment, we wouldn't get very far at all.
I know of two ways in which the concept of rebirth is discussed. One is when ordinary people like you or me think about death and it goes something like this: if someone was, let's say, a habitual abuser of animals, then they will probably come back as an animal.
This is easy to interpret. It's a way of getting them to put themselves in the place of others. Maybe that will change the way they behave towards them.
The other context in which I have heard the idea of rebirth is when it applies to people like the Dalai Lama. When his predecessor died, a search party was sent out to find a young child as whom he would have been reborn. Indeed they found a two-year-old boy who appeared to know certain things that his predecessor would have known. So he was enthroned as the 14th Dalai Lama, and taken from his remote village to the capital of Lhasa to live in the very ancient palace that has been the home of all of them for centuries, and trained in his role by a team of strict tutors.
In his autobiography the Dalai Lama mentions that he is just another monk. Being the Dalai Lama is his role. The role of the Dalai Lama is to preserve and protect the dharma, and the people. When Tenzin Gyatso is asked if he really believes in rebirth, he replies “It's complicated.”
The fact is, there is a continuity in the lives of the different occupants of the title of Dalai Lama. It's easy to understand why, as they all occupy the same home and brought up and educated in exactly the same way. In a very real sense, the Dalai Lama continues to be reborn, and with him the Tibetan people and their buddhist tradition.
What the idea of the Dalai Lama being reborn again and again produces is an exceptionally resilient and united people, unperturbed by inner conflict, and confident in the leadership of someone who is centuries old, the eternal physical manifestation of Avalokiteshvara, of great compassion. The Tibetan people understand this very clearly. Without that understanding, they would have been lost. The continued rebirth of the Dalai Lama is real, with profound and very real consequences.