Every decision can be written as a function of cost and reward. People take possible options, assign them costs, rewards and multiply them by weight of preference, biases, and inclination to gratification capabilities.
Let’s jump straight to example, in a decision “Should I take out the trash now?”, we notice three options:
- Take out now
- Don’t take out now
- Wait for two or three bags
Now, let’s calculate the costs, rewards, and weights
 Take out now.
+1 * 2 = My partner will be happy +1 * 1 = It won't stink in the house +1 * 1 = Take a break to reflect on what I'm working on -1 * 5 = Get up from my work, and lose focus from what I'm working on -1 * 3 = Lose 5min on nonproductive activity ------------- + 2+2+1-5-3 = -3
 Don’t take out now
+1 * 2 = Keep focus -1 * 3 = My partner will be upset -1 * 5 = My partner will punish me -1 * 2 = It will stink ------------- -8
 Wait for two or three bags
+1 * 2 = Keep focus +1 * 1 = Take a break to reflect on what I'm working on -1 * 1 = My parner will be a bit upset -1 * 1 = It will stink a bit -------------- 1
After such a mental evaluation we decide on option 3.
This model has some flaws, or rather people have flaws––what if one doesn’t come up with option three? One will decide on the first option, throw the trashes right away, thus become not optimal. Therefore, it’s very important to doubt every decision and seek different possibilities.
You probably noticed that the decision depends on the number of rewards and costs. People who find it easier to find costs are pessimists. People who come up with rewards easier are optimists. Another factor is weight, people who value the costs more than rewards are lazy, on contrary, people who value rewards over costs are curious.
Passion is another factor that can drive the decision. Passion is a source of infinite rewards. That’s why doing what is your passion is easier. For instance, if your passion is programming, it will be easier to spend your free time learning new programming languages and work on side projects over watching TV––the decision will become obvious.
We are programmed to decide on options that have the highest net rewards. Those rewards should match with our goals, but don’t have to. Sometimes some defect like addiction, bad habit, or complex, is so strong that we act not rationally––even if the costs are huge compared to rewards we still decide on those bad options.
Your partner, parent, supervisor, a friend can help you achieve goals by adding rewards to goals and costs to your bad habits, so your inner evaluator will be more inclined to do what you should do. If you are going to a gym and your goal is to gain muscle mass you should not drink alcohol. You can help yourself by asking your gym mates to punch you if they notice that you were drinking alcohol. If you have a problem with some bad habit, like biting your nails, you can try some medicines like bitter polish, it will increase the cost of bitting nails––thus decreasing the net-reward. Another way is to ask your partner to punish you by not cooking you breakfast the next day when he or she notice that you were biting your nails.
Finding passion in what are you doing can help you during moments of hesitation, when the net reward of doing something is near zero.