Many years ago I experienced a devastating accident. A large magnesium flare exploded next to me and left 70 per cent of my body covered with third-degree burns. While in hospital I acquired hepatitis from an infected blood transfusion. The liver disease increased the risk of complications during the operations I needed, delayed my treatments and caused my body to reject many skin transplants. To make matters worse, the doctors could not identify the strain of hepatitis. After a while the illness subsided, but it still slowed my recovery by flaring up intermittently and wreaking havoc on my system.

Eight years later, while I was already in graduate school, a flare-up hit me hard. After many blood tests the doctor gave me a diagnosis: it was hepatitis C. As lousy as I felt, I greeted this as good news. First, I finally knew what I had; second, a promising new experimental drug called interferon looked as if it might be an effective treatment.

The initial protocol called for self-injections of interferon three times a week. The doctors advised me that after each injection I would experience flu-like symptoms, including fever, nausea, headaches and vomiting. But I was determined to kick the disease, so every Monday, Wednesday, and Friday evening for 18 months I plunged the needle deep into my thigh. About an hour later the nausea, shivering and headache would set in.

Every injection day was miserable. I had to face giving myself a shot followed by a 16-hour bout of sickness in the hope that the treatment would cure me in the long run. I had to endure what psychologists call a “negative immediate effect” for the sake of a “positive long-term effect”.

At the end of the 18-month trial, the doctors told me that the treatment was successful and that I was the only patient in the protocol who had always taken the interferon on schedule. How did I get through those months of torture? Do I simply have nerves of steel? No. Every injection day I deeply wanted to avoid the procedure. But I did have a trick: I love movies, so I decided to motivate myself with movies. Every injection day, I would stop at the video store and pick up a few films. Throughout the day, I would think about how much I would enjoy watching them later. Once I got home, I would give myself the injection. Then I would immediately jump into my hammock and start my mini-film fest. That way, I learned to associate the act of the injection with the rewarding movie experience. About an hour later, the negative side effects kicked in, and I didn’t have such a positive feeling. Still, planning my evenings that way helped me associate the injection more closely with the fun of watching a movie instead of the unpleasantness of the side effects.

The moral of this story? All of us have important tasks that we would rather avoid. We all hate grinding through receipts while doing our taxes, clearing the garden or sticking to a diet. Despite the prodding of conscience, we often would rather avoid doing something unpleasant now (exercising, working on an annoying project, cleaning out the garage) for the sake of a better future (being healthier, getting a job promotion, earning the gratitude of one’s spouse). Of course, in a perfectly rational world, procrastination would never be a problem. We would simply compute the values of our long-term objectives, compare them to our short-term enjoyments, and understand that we have more to gain in the long term by suffering a bit in the short term. Sadly, most of us often prefer immediately gratifying short-term experiences over our long-term objectives. “Later” seems like a rosy time to do all the unpleasant things in life, even if putting them off means eventually having to grapple with a much bigger jungle in our garden, a tax penalty or an unsuccessful treatment.

It would be nice if we were more rational and clearheaded about our “should”s. Unfortunately, we’re not. How else do you explain why millions of gym memberships go unused or why people risk lives to write a text message while driving? This is where behavioral economics enters the picture. In this field of study, we don’t assume that people are perfectly sensible, calculating machines. Instead, we observe how people actually behave, and quite often our observations lead us to the conclusion that human beings are irrational.