Toward the end of his life, in an essay entitled “Topic of Cancer” in 2010 in Vanity Fair, Christopher Hitchens answered his own rhetorical query poignantly: “To the dumb question ‘Why me?’ the cosmos barely bothers to return the reply: Why not?”

The cosmos has never been particularly loquacious with its intentions, often requiring Brobdingnagian-sized ventures—from particle accelerators and space telescopes to genome and connectome projects—to tease out its deepest secrets. Can the same be done for death? A number of scientists and Silicon Valley billionaires think it can.

Oracle co-founder Larry Ellison, for example, has given more than $430 million toward antiaging research because he finds the quiet acquiescence of mortality “incomprehensible.” XPRIZE entrepreneur Peter H. Diamandis co-founded Human Longevity, which, in conjunction with StartUp Health, launched the Longevity Moonshot, whose mission is “to extend and enhance healthy life by 50+ years and change the face of aging.”

Google co-founder Larry Page launched a biotech company called Calico, which aims to extend the human life span by a century. Calling it “a longer-term bet,” Page said he was confident they “can make good progress within reasonable timescales with the right goals and the right people.” One of those people is Ray Kurzweil, the scientist and futurist (and now a director of engineering at Google) who thinks that if we can survive until the 2040s, we can “live long enough to live forever.”

PayPal co-founder Peter Thiel created Breakout Labs to fund scientists and start-ups that include some working on achieving immortality, and he invested $3.5 million in the Methuselah Foundation, co-founded by Aubrey de Grey, the biomedical gerontologist whose Strategies of Engineered Negligible Senescence (SENS) treats aging as an engineering problem to be solved at the cellular level by reprogramming cells to stop aging. A tireless promoter of the belief that our generation will be the first to achieve immortality—or at least to live indefinitely—de Grey is on record claiming that the first human to live 1,000 years is alive today. If you've seen any television show or documentary film on aging, you've seen the inimitable Aubrey de Grey, with his waist-length ponytail and Methuselahlike beard and baritone British accent. I've met Aubrey and shared a beer or two with him (if there is a fountain of youth in de Grey's world, it bubbles with beer) as he leaned in to bend my ear on the latest shields against the grim reaper's scythe.

I like beer, but I have my doubts. First, the second law of thermodynamics is paramount in the universe, so entropy will get us in the long run, if not the short. As the renowned astrophysicist Sir Arthur Stanley Eddington noted in 1928, “If your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.”

Second, extrapolating trend lines far into the future is problematic. Accelerating change may not continue at those rates nor apply to all technologies. Downsizing of computers from room size to pocket size is one thing; it is quite another to go from pocket size to cell size.

Third, according to a 2007 review paper in the journal Clinical Interventions in Aging entitled “The Aging Process and Potential Interventions to Extend Life Expectancy,” there is no single cause of aging and more than 300 theories for why cells deteriorate and stop dividing. The authors are thus led to conclude that “to date, no convincing evidence showing the administration of existing ‘anti-aging’ remedies can slow aging or increase longevity in humans is available.” And the SENS Research Foundation Web site admits: “No currently-available medical intervention or lifestyle choice has been shown to affect the basic human aging process.”

Still, hope springs eternal, and as Bill Gifford reported in last month's Scientific American (“Living to 120”), there are some promising hints of antiaging properties of the diabetes drug metformin, which the FDA approved in 2015 for a clinical trial. If it helps more of us live healthy lives up to the ceiling of some 120 years, that would be welcome progress, but let's not delude ourselves into believing radical life extension is around the corner. Our bodies are mortal, at least for now, but our genes are immortal as long as our species continues, so we owe it to future generations to create a sustainable planet and civilization.