[Global Change: 2311] Re: Cost/benefit of human extinction

On Dec 28, 9:07 am, Tom Adams <tadams...@xxxxxxxxx> wrote:
> The value of a human life is around 10 million these days.
>
> Based on that,  I figure that we can't justify spending 500 billion to
> avoid extinction in 591 years.  Sometime around July 4th, 2598 to be
> exact.

I'm greatly reminded of a calculation Mark Twain published on the
length of the Mississippi river. Any sum compounded at a any positive
rate of return will eventually exceed any fixed value. So?

It is not worth spending US$0.01 to prevent extinction in year X. Year
X will depend on the rate of return and the stated value of human
species. at US$6*10^16

At a 10% real return, and US$6*10^16 valuation, X is about 2480.
Amusing, and not very useful.

Think also about the last year before extinction. What rate of return
would you accept for a loan that would never be paid, as both the
borrower and the lender would be dead? What rate of inflation might be
expected, if money not spent will expire worthless? How could you
define real rate of return?