I found this essay on why we do things that are bad for us really interesting. First, I learned the word “akrasia”, which means “the state of mind in which someone acts against their better judgment through weakness of will.” Second, this is not exactly a new thing. From Romans 7:18–19:

For I have the desire to do what is good, but I cannot carry it out. For I do not do the good I want to do, but the evil I do not want to do—this I keep on doing.

Anyway, I thought this was helpful advice:

To achieve your goals, it can be more effective to put into place a defined plan that doesn’t let you reconsider. The psychologist Peter Gollwitzer called this an implementation intention: come up with a specific if/then statement that helps you achieve your goal. If it’s Tuesday, then I will go to yoga class; if I buy spinach, then I will make this smoothie for breakfast the next morning.