Time is more important than money. You think that you know this, but you probably don’t act on it as much as you could. If you spend your time buying material things then you are using up the one thing that can make you happy (time) on things that definitely don’t make you happy (stuff).

In terms of happiness, time matters a lot more than money. The most important factors of happiness — the quality and intensity of your relationships, how often you have sex, how much sleep you get — all come from an investment in time rather than money. (For those of you who think money buys sex, stop yourself: “It's true that money impacts which person you marry,” says professor of economics David Blanchflower, “but money doesn't impact the amount of sex you have.”)

So if you’re considering taking a job that requires long hours so that you can make a load of money, don’t do it. Authors of the book Your Money or Your Life, Joe Dominguez and Vicki Robin, present a fresh way to think about this tradeoff:

“Try turning around the old maxim ‘time is money’ and look at it this way: ‘We pay for money with our time.’ Those hours on the job (or our partner’s hours on the job) are what bring money into our lives. Money, by definition, is simply something for which we choose to trade hours of our life — what we’ll call ‘life energy.’ While money has no intrinsic reality, our life energy does — at least to us. It is precious because it is limited and irretrievable, and because our choices about how we use it express the meaning and purpose of our time here on earth.”

This way of thinking gives you a more concrete way to value your time. And, once you start thinking this way, you can see the astounding ways that people undervalue their own time.

While you’re thinking about what is worth giving up your time for, take a look at the research about materialism; fantasizing from your cubicle about the grand purchases you will make actually makes when you finish work will actually make you UNhappy.

“Seeing the BMW may make you feel unhappy, but psychological studies show that obtaining the BMW would not make you happy,” says Gregg Easterbrook, psychologist and visiting fellow at the Brookings Institute. And the more emphasis one puts on materialism the more likely that person is to be depressed and anxious. So look, it’s a wild goose chase with the stuff — you will never buy the thing that’ll set you on the happiness track.

Most people, when looking back on their lives, wish they had done things that cost time, not money. The Royal College of Surgeons in Ireland, has conducted long-term research about terminally ill patients. The findings: “It is much more common for people to regret not the things they did, but that there were so many things they didn't have the time to do.” So consider seriously the idea of making more time for yourself by agreeing to earn less money. And if you have to work a lot, use your money to buy time — takeout food, a cleaning service, a personal assistant.

Think of all the time you spend planning how you spend your money — balancing your checkbook, preparing taxes, reading financial advice. Spend at least that much time and energy planning how you will spend your hours. People know that if they don’t pay tons of attention to how they spend their money then they’ll never be rich. But think about this: If you don’t pay tons of attention to how you spend your time, you’ll never be happy.

Hat tip: Occupational Adventure