Gravity and Levity

http://gravityandlevity.wordpress.com/

An interesting blog.

For example:

... my eight lifetimes. In it, I postulated that we measure time relative to our age, and as a result each length of time wherein our age doubles carries an equal psychological weight. There’s nothing scientific about this discussion — it’s just an idea. But it has absolutely changed the way I think about my life and the process of getting older. At the risk of being a shameless self-promoter, I highly recommend reading it.

The argument about “my eight lifetimes” can be summarized this way: in your life you will undergo roughly eight major transformations. That is, you get eight “lifetimes” during which you become a new and different person. If you’re reading this blog, chances are that you’re already on your sixth or seventh. This is not to say you have one foot in the grave: having an entire lifetime ahead of you is still a big deal. For me, a 25-year-old, the two remaining lifetimes are the transformation from a 20-something-year-old to a middle aged man, and then from middle age to an old man. Both of those time periods are a big deal, and each of them contains plenty of living to be done. I just imagine that the time period between age 6 and age 12 was a similarly big deal.

All of this brings me back to the Gompertz Law of human mortality. The Gompertz Law is already an extraordinarily fair statement: no one escapes mortality, which becomes exponentially more probable in old age. But if you subscribe to my idea of time progressing relative to itself (of life being composed of “lifetimes”), then the consequence of the Gompertz Law is an almost extreme level of fairness. Look at it this way: about 96% of people survive to age 48 (the beginning of the “eighth lifetime”), but only 4% make it to age 96 (the end of the eighth lifetime). If you try to come up with an equation for probability of survival vs. number of lifetimes lived, you get an almost absurd exponential within an exponential within an exponential.