A major theme of the book is that there is a strong modern interest in combating aging. But that's not a point we disagree on. The disagreement point seems to be how much historical interest there was.

Your points 2 and 4 above in that regard are not accurate. And Stipp's book reflects that. In the very first chapter he notes how early 20th century gland implantation attempts were taken seriously by major, respected scientists. He includes as examples Charles Brown-Sequard. I agree that there's more interest in anti-aging than there has been in the past, but the claim that prior attempts at anti-aging were not considered worthwhil endeavors or were restricted to the fringe simply aren't accurate.

This is asinine. Science is a convergent, not a divergent, endeavor. Increased knowledge in one field necessarily alters or amplifies the impact of knowledge in another. I said nothing to contradict this and gave several examples of it being affirmed.

I don't understand what you mean by this, and all attempts to parse it don't seem to produce responses that make sense as a response to my remark. Can you rephrase or expand what you mean here?

This is a testable hypothesis and it has already been falsified. We share cellular metabolism with calorie unrestricted organisms, and not with CR-organisms.

The hypothesies has definitely not been falsified. There's evidence against it. But that isn't the same thing at all. It isn't just our cellular metabolism that matters in this context. We don't fully understand how reservatrol extends lifespan. We know that it has effects similar to caloric restriction, but without a better understanding of how it is doing that we don't know. This is also but one of a variety of things that could go wrong. Consider for example that we use a reservatrol-like compound for a while and then it turns out that something in the human diet that isn't in our lab environment interferes with it. These are but two examples.

Furthermore, while human lifespans are longer than most mammals (not all but most), they certainly aren't by any means exceptional for even warm-blooded organisms in general.

In general maximal lifespans are roughly correlated with size in mammals. But, compared to most large mammals great apes have a larger lifespan even given good medical care to those species. Of all the great apes, this disparity is strongest with humans. Chimpanzees, one of humans closest living relativies, have a maximal lifespan of around sixty years, approximately half that of the human. Chimps size is smaller than humans on average, but not by that much. Similarly, bears are normally larger than humans and the other great apes, yet the oldest age for bears is around 45 years. Humans seem to have adopted some aspects that are pushing our maximal age up that aren't in most other mammals.

With the topic having received, finally, mainstream attention -- we've gone from the periodic instance of the isolated potential investigation to the spaghetti method: throw everything at the wall and see what sticks.

Sure, that's more likely to work. But that's a far cry from every probable world-line from here either involving civilizational collapse or absolute success. Consider the possibility that we spend thirty years trying to throw all the spaghetti on the wall and none of it sticks It may be that I'm reflecting my own biases since I'm in a field (math) where lots of smart people can spend a lot of time working on a problem and it can still take hundreds of years to solve.

Nowhere did I ever make that claim.

Yes, I see. You didn't make this claim. I misinterpreted your current age. The claim being made is weaker than I thought, although still a very strong claim.

I don't fully understand how your last paragraph is relevant to the bit it is responding to.