Kass is specifically opposed to improving medical technology that will extend and improve lives. He believes that death is all that makes life worth living.
From Age-Retardation: Scientific Possibilities and Moral Challenges: "If we remain at our prime, in full swing, for decade after decade, and even for centuries, the character of our attitudes and our activities would likely change significantly,"
February 23, 1971, New York Times quotes him predicting, "If efforts to understand and alter the aging process are pursued full tilt, by the end of this century the 'useful' life span of some individuals may be extended 20 to 40 years."
"The young generation of today, he asserted, is the first to grow up without fear of lethal diseases. Hence its members, as a whole, have neither faced death as a real threat to themselves nor seen it take a certain number of their contemporaries, he said. Dr. Kass argued that people were therefore becoming less and less conditioned to accepting death as a natural and merciful way to terminate the aging process."
From an April 2004 interview at Sage Crossroads: "Time is a gift, but the perception of endless time or of time without bound in fact has the possibility of undermining the degree to which we take time seriously and make it count."
Just Google "Leon Kass Instapundit" or "Leon Kass Virginia Postrel" for seriously scary thoughts coming from Kass. Prof Reynolds and former Reason Editor Postrel really, truly despise Kass and his views and have been opposing him and publicizing his malevolent opinions and influence for a very long time.