Time is the ultimate non-renewable resource. To get the most out of life, it behooves us to conserve it and to be efficient when consuming it. In this entry, I will explain a core philosophy about time.

Every day we face opportunity costs representing the sacrifice involved in choosing one course of action over another. If someone buys a fancy car, they may be sacrificing money that could be put toward retirement in favor of more luxury in the present. If you choose to leave your current job and start your own company, you may have balanced ditching the commute and being your own boss against fewer fringe benefits and less job security.

Such costs often come in the form of time, rather than money. If I choose to play a video game, I balance the benefit of a relaxing evening against the cost of two hours that I will never have back for something more productive. If you take the freeway to work, it might be a relatively simple route at the cost of severe traffic, at least compared with twisty side roads. Everything involves compromise!

Whether you see the pursuit of money as an end in itself or simply as a tool to trade your labor for things you need, there’s no denying that it plays a significant role in everyday life for many people. The phrase time is money often shows up in film and television where an impatient executive or used-car salesman tries to rush a decision. This is actually going to be useful, so bear with me.

Let’s discuss another idiom: money doesn’t grow on trees. Money is generally a finite resource for many of us, not simply plucked from the vine. This tells us not to squander our hard-earned cash, at least not without establishing a solid foundation for ourselves, such as having a roof over our heads.

Why doesn’t time get the same treatment? If we combine the two idioms—if time is money and money doesn’t grow on trees—we come to the mantra time does not grow on trees, which tells us that your time has value! It doesn’t matter if you’re paid $100 per hour, $10 an hour, or not working for pay. An hour spent talking to the folks who showed up at the front door is an hour not spent with the family. Before you dedicate your time to an endeavor, make sure that endeavor deserves it!

This applies to social situations, too! I can spare two or more hours to talk to my best friends on the phone, because they’ve stood by me and shown their support; they would do the same for me. Meanwhile, if a survey marketer calls you up for a 30-minute survey, you don’t owe them anything—why not spend that time doing something that benefits you or the ones you love?

In this post, I examined a core mantra about time. In a future post, I will explain another important place where we can apply it.