If the modest trend in increased life-span for 60 year-olds were to continue for another four centuries, 60-year-olds would have average life expectancies of 120 years of age!

If marriage and child-bearing occur at young ages, someone who has 30 descendents at 80 could have 62 descendents at age 100 . . . and 126 at 120. Even those who marry and give birth at more advanced ages could have 62 descendents at 120.

With so many more years to gain the benefits of compounding the value of a person's investments, we can expect that it will be easier than ever to accumulate substantial wealth. Buy one piece of property on a lake somewhere, and in an increasingly crowded world you can sit back and enjoy the thought that they aren't building much more lakefront property any more. Be cautious about oceanfront property, however; violent storms and melting polar ice caps could flood your land!

Commercial property investments for retailers will be similarly lucrative if you buy where everyone will want to be for the next several decades. Safe bets like spots overlooking Central Park in Manhattan and Waikiki beach views from up the mountain in Honolulu will probably create many trillionaires in the future.

You can now buy index funds of several thousand of the largest companies in the world. These stocks compound in value around 5 percent a year in real terms. That means doubling in purchasing power every 15 years. Put $100,000 into such an index fund at age 30, and the value of your portfolio's purchasing power in today's dollars will be $6,400,000 at age 120.

What about your future income potential? Average productivity gains over long periods of time have been about 3 percent a year. Incomes tend to track the rate of productivity gains so we can use this statistic to estimate how much purchasing power will increase in the future.

At that growth rate, your purchasing power doubles every 24 years. That is almost seventeen doublings over 400 years.

For someone who currently earns $35,000, four hundred years of such progress would expand income to $7.5 billion in today's purchasing power. If that occurs, chances are that only those who really want to work will be doing so for very long.

Or perhaps the work week will shrink for most people to just a few minutes. Someone who worked 30 minutes a week would earn $94 million a year. I think I could get by on that. How about you?

How might you earn this much for so little effort? Someone who developed a great computer program for investing money might need to spend only 30 minutes a week overseeing the program's application. Money managers are already paid in the millions if they are any good. A great one could certainly expect to earn $94 million a year today.

How would most people earn that amount? I suspect that computer technology will develop to such a point that anyone will be able to establish a profitable specialty that's enormously valuable to others. What will your specialty be?

Copyright 2008 Donald W. Mitchell, All Rights Reserved