Economist Writing Every Day

Economists rightly make a big deal out of specialization and trade. They proceed to go one step further and say that it’s better to pay someone else to perform some service, even if you can perform it yourself. One the assumptions underlying this advice is that time and money are both fungible and convertible.

How are economists right and wrong about the convertibility of time and money? In one sense, we can change how much we work and change how much income we have. That seems plain. But it also requires some start-up costs to have an easy go-to means of earning more income. For example, Uber drivers are registered with Uber already.  Joe from the street can’t start driving tomorrow without substantial preparation.

If economists are wrong about the convertibility of earned time and earned money, then they still have standing. We all have an endowment of time, if not money. But there are plenty of goods that have a money price and a time price that have an inverse relationship.  The advantage of having a time budget is that you can offset some of the money price of goods with time such that more of the money budget can be spent otherwise.

For example, I had to buy a new golf cart battery. One option was to spend $2,400 for a guy to come replace my old battery for me. The other option was for me to spend $1,500 and one evening to do it myself. Given that I typically do chores in the evening anyway, the time-cost to me didn’t feel all that imposing.

Further, if I free up some time, then what happens to it? I can leisure. That’s what economists call any time spent that isn’t working. But after that leisure, it’s gone. There some saving your time for later in the form of bringing other chores earlier in time. But there’s certainly no allowing your time to earn compound interest. That’s where the advantage of self-service really shines IMO. I can give up $900 and enjoy one evening of leisure. Or, I can given up an evening of leisure, put the savings into an investment account, and then reap double the evening’s worth seven years later. Then I’ll have two nights of leisure rather than one. To me, that’s the biggest difference between time and money. I can earn interest on my money in a way that I can’t earn interest on my time.