The most important or significant hidden truth about human life is be happy forever, take care your family and children, for helping other people and make a world better place and to be for religion.
Dear friend the ultimate, significant and hidden truth of life which can never be denied by any one on this earth is our destined death! No body knows when it will come, but every body is sure that one has to die one day, which is the ultimate truth of the life! Thanks !