We got good at preventing and treating heart attacks and stroke. People lived longer and they got cancer. We got really good at treating cancer and now people get dementia illnesses.

What happens when we get good at treating dementia?

(Obviously, "good at treating" is with respect to what went before, not where we want to be.)

A life expectancy of 80 or 90 where you are active until the last six months of your life is a win compared to keeling over at 55 from a stroke or heart attack. The fact that life expectancy is not 100 or 1,000 doesn't mean that it's not worth investing in improving quality of life and life expectancy.

What happens when we get good at treating dementia is that your children will be able to have intelligent conversations with their great great grandparents (or you will be able to have intelligent conversations with your great great grandchildren).

Then perhaps "better at" is a more apt phrasing than "good at"?

No, because we actually are good at treating a lot of cancers. It's remarkable. We're good at treating heart disease. It's remarkable.

No I'm suggesting that the body is a complex system and if you solve one component of the problem, another component ultimately fails until you run out of components (hint, just like software)

Every time a cell divides, it has a chance of turning malignant. Live long enough and one of those cells will win the cancer lottery and take you down if you don't catch it in time. Many forms of cancer are symptom-free long enough for this to happen (pancreatic for example) and we do not yet have the technology to easily detect this until it's late in the game.

And that's just one way to go. Then there are aneurisms and all sorts of other odd bodily defects that will eventually manifest.

Ageing is tough. That said, eat right, exercise, and get enough sleep, and you'll stand the best chance to max out your time clock.

Yeah, if man were meant to fly... Every generation has a few people like you.

Anyway, some people like to work on tough problems. No one said it's going to be easy or that progress won't come slowly. There are 7 billion people on the planet. If you can help with early detection of pancreatic cancer, for example, you will impact many lives.

So, just like software, we should throw in the towel and give up?

It's true that on a long enough time line we will all inevitable get cancer or some degenerative disease, fine. But does that mean that we should just give up and not attempt to further prolong life? More importantly, curing some prolific diseases like dementia, arthritis, and osteoporosis could dramatically improve not just quantity of life but quality of life as well.

The "one-hoss shay" syndrome: (see [0])

http://www.williamson-labs.com/one-hoss-shay.htm

Then why did you include the follow-up statement as a parenthetical addendum to your initial statement regarding the second law of thermodynamics?

Given a shower and an infinite lifespan (no death from aging), you will eventually trip and die in the shower. Given enough time and a set of possible events, all of those events will unfold eventually. So I don't see what's so damning about the inevitable cancer, since you seem to hint at that we might get the technology to easily detect them in time eventually.