The Last Lecture is the book-length expansion of the talk that Randy Pausch gave to explain his attitudes towards his diagnosis of terminal cancer. Pausch used his limited time to promote the ideas of living fully, the lessons he wanted to teach his children, and how the pursuit of his own childhood dreams informed and shaped his life. While the subject matter is inherently grim, Pausch deliberately takes a positive view, refusing to be defined by his disease and instead allowing it to make every moment a joyous event.
I'm dying and I'm having fun. And I'm going to keep having fun every day I have left. Because there's no other way to play it.
(Pausch & Zaslow, The Last Lecture, Google Books)
Pausch also talks about making the most of time, whether a person is dying or not, because to do anything else is to waste the gift of life. Pausch believed that living was itself the promotion of ideas and ideals, and leaving something of himself behind for his children was more important than wasting time searching for a cure that did not exist. In the end, the topic of The Last Lecture is life itself; Pausch was a fervent believer in the dictum of "living every day as if it is your last," because he knew that for him, that day was close.