George Carlin's philosophy for old age emphasizes enjoying life and maintaining a youthful spirit as you age. The summary discusses how children look forward to getting older in fractions but once adults hit milestones like 30, 40, and 50, aging is no longer something to look forward to. However, the piece recommends making it to 60, hitting 70, and even becoming a kid again once passing 100 by keeping your mind active, laughing often, and surrounding yourself with loved ones and activities that bring you joy.