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Memories of the 28th Century


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Recently, someone wondered how people feel about mortality. I have written about that in the past, so I mostly just referred to those, but there a few parts of the question that I think deserve a little more consideration. One thing is that it is sometimes said that people start dying immediately after birth. I disagree with that, and I think that many medical experts would also disagree. Humans continue to develop after birth, and cells are replaced as long as people are healthy.

It would be more accurate to say that people start to die, when their cells cease to reproduce, and that can happen at different times, depending on the individual’s genes and experiences.

On the genetic level, many, or maybe most, genes are designed to run once during development, and after they operate a methyl group is added, so that gene will not operate again. A variety of traumatic experiences can cause the methyl group to be removed, so the gene will run again; those can include some physical damage and extreme cold. Even if that happens, the telemeres that hold the ends of the chromosomes together unravel with each cell reproduction, and that eventually leads to cell death.

When cells start dying, skin loses elasticity, so wrinkles form, and pigment spots start, so people start looking old. The same aging cells results in injuries and disease that would not have been problems earlier. Therefore, people of the same age vary greatly in their apparent age. There are people who are about my age who look decades older, and I have met people fifteen or twenty years younger than I am who look older than me.

I think that part of the reason for the differences in apparent age is a result of attitudes toward aging and death. Some people never come to terms with their own mortality, while others are quite comfortable with it. I have also noticed that some people seem to have a good idea of when they will die, and most of those people are fairly accurate, but that degree of foreknowledge does not relate to the level of comfort with their own mortality.

But that foreknowledge of one’s death suggests that on the subconscious level people may be aware of their genetic make up that will determine their lifespans. There are mystical implications, but I won’t go into that. This has again gotten me wondering about Li Ching Yuen, the Chinese man who lived 256 years. With one of his students, he wrote a book, The Secrets of Li Qingyun’s Immortality, and that appears not to be available from the online sources; although a number of books about him are available. I wonder what he thought about his mortality when he was younger. The descriptions of the book that I have seen mention Taoist thinking in it, so he may have lengthen his life through thoughts and activities. There are people who doubt the date of birth of Li Ching Yuen, but apparently he was sent birthday greetings for his two hundredth year by the Emperor in 1877.

Some of the foremost medical researchers specializing in longevity do not not think that there is an upper limit to human lifespan. On the other hand, there are people in that field who think that humans are already at the limit. There is research going on at SENS Research Foundation; Aubrey de Grey is their chief science officer. They do not have any products, but they give information that is worth knowing. One thing that I found interesting was that while genes play only 25% of the determination of lifespan up to age 75, genes are much more important for aging beyond that point.

Another interesting factor is the way that actuarial science handles the matter. Actuaries say that there is a one third of one percent per annum of dying from random crime or accident. That suggests that the upper limit of human age is 300 years. We will see.