Time Enough for Love;

The capstone and crowning achievement of  the Future History series, from the New York Times bestselling Grand Master of Science Fiction...

Time Enough for Love follows Lazarus Long through a vast and magnificent timescape of centuries and worlds. Heinlein's longest and most ambitious work, it is the story of a man so in love with Life that he refused to stop living it; and so in love with Time that he became his own ancestor.