Somewhere, on a blog that I can't remember now, there was a question on the efficacy of savings over very long periods of time; should life extension protocols actually be found that work.

Someone used a quote from the The Notebooks of Lazarus Long:

$100 placed at 7 percent interest compounded quarterly for 200 years will increase to more that $100,000,000 - by which time it will be worth nothing.

Actually, someone has already tried this: Benjamin Franklin.

In 1790 he left in his will 1,000 pounds or about $4000 - a good sum in that day - and gave directions on it's investment, for the next 100 years. Despite various setbacks and changes in investment over the next 200 years the money grew to be more than $5,000,000 by 1990 - substantial increases on the principal, even when inflation is factored in.

This works out to about 3.7% annually compounded interest.

So, why would Heinlein have Lazarus, an immortal, say such a thing?

Well, it's clear from the books that Woodrow Wilson Smith, aka Lazarus Long, was a bit of a rogue. One can imagine him on some distant frontier planet, trying to coerce some earnest young and upright rube into joining a card game. It's payday and the boy's flush - but on his way to the bank to save that money, mindful of what his mother told him. He's just stopped in for a sarsaparilla, but Lazarus has this chair open at his table in the back of the saloon...