I think death is the most important of all truths about Life. It is the most important truth of life. You can understand life itself better if you begin the process of understanding from death.
For example, I was reading the life history of Eric Berne, whose book "What do you say after you say Hello" I had read a bit. (That book is another story in itself). Now he wrote so many books. If you read that book "What do you say after you say Hello", then you will realize that he had reached heights of understanding of people and their behavior. That book he just completed before his death, and was very happy the way it turned out. He had just sent the manuscript for publication, and then only a few weeks later he got one heart attack, got admitted in hospital, and he died.