What is the relationship between money and happiness? It's the subject of much debate, but the answer is not as clear cut as most believe.

This is a topic personal finance columnist Jonathan Clements considers in his practical, understandable and valuable new book, “How to Think about Money.”

Clements refers to academic studies indicating that money can indeed buy happiness, but not nearly as much as expected. He suggests that, contrary to some current thinking on the matter, we value our possessions more than experiences. Working hard toward our goals can bring great pleasure, but achieving our goals is often a letdown.

The main thrust of Clements' book is not to settle philosophical questions but rather to advocate practical ways to maximize financial independence — a sure path to happiness if there ever was one.

A major part of that challenge, he points out, is that everyone is living longer. The median life expectancy for those born in 1951 is age 84 for men and 87 for women. Among today's 65-year-olds, about 25 percent will live to at least 90, and 10 percent to at least 95. In other words, your retirement could easily last 30 years — a long time to need resources for a comfortable retirement.

Given the increase in life expectancy, Clements argues that we must reorient our thinking in these ways:

Get on the right financial track as early as possible in order to achieve some measure of financial freedom.

Use that freedom to focus on work you are passionate about.

Invest for the long term, meaning a lifetime commitment to stocks.

Worry less about dying, and more about living.

A decision he recommends is one I've made in this column many times: Postpone applying for Social Security benefits. A significant percentage of people file for benefits at age 62. If you postpone filing for benefits until age 70, your benefits will increase by approximately 76 percent. You will benefit, of course, but your surviving spouse's benefits will increase as well. (As William Bernstein states in his introduction to the book, “Uncle Sam offers the best pension plan that money can buy: deferring Social Security until age 70.”)

Clements also suggests you consider buying longevity insurance and immediate fixed annuities that pay lifetime income.

For those early in their careers, Clements recommends making an effort to postpone purchasing unnecessary possessions and concentrate on saving as much as possible in order to take advantage of compound growth. He believes that, regardless of stock market price volatility, your focus should be on investing in common stocks. Don't hesitate to invest when prices fall. That is the best time to be investing in common stocks.

He feels strongly, as I do, about investing primarily in low-cost, globally diversified index funds, primarily in U.S. He believes that most investors who try to outperform index funds by actively investing will incur additional annual costs of approximately 2 percent per year, and in the long-run they will trail the market by approximately the same percentage.

Many individuals, especially early in their careers, don't take advantage of the employer match associated with 401(k)s and other defined contribution plans. Even if it is a strain on your finances, you should always make the maximum contribution to obtain the employer match. It is almost impossible to find a better investment.

When you do reach retirement, you can modify your portfolio and increase the percentage of bond index funds. But you should still maintain a significant percentage of low-cost diversified global common stock index funds.

Your goal should not be to get rich but rather to have enough assets when you reach retirement to lead the life you want.

Elliot Raphaelson welcomes your questions and comments at raphelliot@gmail.com.