While the transhumanism movement is making progress, it isn’t without its skeptics. Some don’t think it will ever work the way we want it to, because it asks science to turn back a natural process of aging that has an uncountable number of manifestations. Critics of anti-aging research envision any number of dystopian futures, in which we defeat many of the causes of death before very old age, leaving only the most ghastly and intractable — but not directly lethal — maladies.

Lest you think this concept is limited to snake-oil salesmen and science-fiction writers, the idea that aging is not inevitable is now in the mainstream of modern medical research at major institutions around the world. The journal Nature dubbed research from the University of California at Los Angeles a “hint that the body’s ‘biological age’ can be reversed.” According to reporting by Scientific American on research at the Salk Institute for Biological Studies: “Aging Is Reversible — at Least in Human Cells and Live Mice.”