Tech-obsessed 40-year-olds are hilarious cocktail party conversationalists. After attending one Aspen Ideas Festival, they become relentless advocates for some new technology they are sure will change humankind for the better. “Genomics is going to revolutionize longevity,” I was told not too long ago with great enthusiasm.

“True,” I replied, “but who wants to live to 120?” My conversation partner clearly did: “If I can be healthy and active, why wouldn’t I want more years on Earth?”

I could think of a few reasons.

The recycled air in his private plane may have altered his ability to clearly consider the first objection I offered, but the 99.999 percent out there who don’t have their own jets will clearly understand. Who can afford to live longer, I asked. He countered with the suggestion that people will work longer and support themselves, thanks to advancements that will free humankind from the debilitating limitations of aging. A lovely luxury-thought, I pointed out, if you are living your passion as a celebrated, well-compensated architect with cheerful co-workers. The janitor at the local big-box store with the grumpy boss may not feel the same way about mopping floors for 40 more years so he can afford his electricity bill when he is 107.

And what would happen to marriage and childbirth, I wondered. Getting and staying married have proven increasingly difficult ideas to sell to even the most lovestruck 30-year-olds – and they are only trying to imagine a 50-year stretch together. Who is going to sign up for the possibility of 90 years of so-called wedded bliss? Men won’t marry until 100, leaving women, still bound by the biological limitations of fertility, to perpetuate the human race as single mothers. Maybe scientists will engineer a woman’s ability to give birth at 90, but who wants to spend the last decades of her life at the circus and trying to get her kids into college?

The fabric of polite society would also tear. These days, 60-year-old women report a sharp decline in caring about what other people think. Eighty-year-old women tell you exactly what they are thinking, which often doesn’t go well. Does anyone want to find out what happens when 116-year-old women are roaming around free to express themselves?

“Well,” he interrupted, trying to redirect, “there is so much I would want to do and see — and have more time for.” He gave a list: countries to explore, the next artistic masterpiece to enjoy, maybe taking a flying car for a spin, or vacations on Mars. I couldn’t think of anything less interesting to live longer for, I told him, than Hunter Biden’s next gallery opening or a $5,000-a-night hotel room with a view of vast stretches of red dirt. And would we all really do that much more with more time? Or would we simply be 118 instead of 88 when we offered “do as I say, not as I did” advice about seizing the day to the younger generations?

There is an additional problem with the body living longer. The mind and spirit inhabit it, and they would grow weary of all those added years, even if the lower back wouldn’t. Life could be a ceaseless buffet of goodness and joy, and human beings would still wonder what else was on the menu. People divorce supermodels, after all.

I am in favor of living better, but not necessarily longer. Ridding the elderly of Alzheimer’s, receding hairlines, and hearing loss seems like a great idea if we can tweak the genome. But even the miracles of science can’t convince me that living to biblical ages will benefit us. We jump too quickly to become cheerleaders for tech innovation, the unintended consequences of which we rarely consider before charging forward. Facebook was a new idea once upon a time, too. People probably talked about it giddily at cocktail parties, imagining the myriad ways it would bring everyone together and make the planet better.

Consider 40 more years of social media posts in your life, and the argument for tempered enthusiasm around new technologies is made.