The bias toward the near

Someone is biased toward the near with respect to money iff for any positive number N, the "strength" of her desire for receiving N dollars at T is greater, the closer to the present time T is.

Someone is biased toward the near with respect to pleasure (/pain) iff for any positive number N, the strength of her desire for experiencing N hedons of pleasure (/desire for avoiding N dolors of pain) at T is greater, the closer to the present time T is.

• If X's desires (over time) can lead to a "sure loss," and X can foresee this ahead of time, then X's desires are irrational.
• If X is biased toward the near, then X's desires (over time) can lead to a sure loss, and X can foresee this ahead of time.
• Therefore, If X is biased toward the near, X's desires are irrational.

The bias toward the future

Someone is biased toward the future with respect to money iff for any positive number N, the "strength" of her desire for receiving N dollars at T is greater if T is in the future than if T is in the past.

Someone is biased toward the future with respect to pleasure (/pain) iff for any positive number N, the strength of her desire for experiencing N hedons of pleasure (/desire for avoiding N dolors of pain) at T is greater if T is in the future than if T is in the past.

I will flip a fair coin, and pay you X dollars if heads, Y dollars if tails. The payoff of the flip is equal to the amount of money I give you. The EXPECTED payoff is, roughly, the average payoff you get if we play this game a large number of times. It is equal to .5*X + .5*Y.

If X = 0 and Y = 20, then the expected payoff is 10 dollars.

I offer you a choice. Option A: play the game with X = 0 and Y = 100. Option B: play the game with X = 40 and Y = 55.

Thesis 1: It is sometimes rational to chose the option with the lower expected payoff, when that option involves less risk. (One way for it to involve less risk is for the worst possible outcome, if you chose that option, to be better than the worst possible outcome of your other option.) It is rational to be risk averse with respect to money.

If each of two situations is equally likely, and the amount of pain you experience in situation A is X dolors, and the amount of pain you experience in situation B is Y dolors, then the expected amount of pain is equal to .5*X + .5*Y.

Thesis 2: It is sometimes rational to chose the option with the higher expected amount of pain, when that option involves less risk. (One way for it to involve less risk is for the worst possible outcome, if you chose that option, to be better than the worst possible outcome of your other option.) It is rational to be risk averse with respect to pain.

• expected amount of pain that you care about as of Monday, no pills: .5*360 + .5*180 = 270 min.
• expected amount of pain that you care about as of Monday, blue pill: .5*331 + .5*211 = 271 min.
•  
• expected amount of pain that you care about as of Wednesday, blue pill: .5*91 + .5*211 = 151 min.
• expected amount of pain that you care about as of Wednesday, both pills: .5*121 + .5*181 = 151 min.

1. If it is rational to be risk averse with respect to pain and to be biased toward the future, then it is rational to take both pills.
2. It is not rational to take both pills.
3. It is rational to be risk averse with respect to pain.
4. Therefore, it is not rational to be biased toward the future.

The Scheduling Problem and Meager Returns problem for future-biased people.

The no-regrets premise: if an agent has full and accurate information about the effects of the options available to her, then it is rationally permissible for her to avoid options she knows she will regret in favor of ones she knows she will never regret.

< 

What is the argument?

< 

Scenario: Fine dining, known deadline. Jack is a "regret-avoider": if, for each of his options, he knows whether he will ever regret it, then he always chooses an option he knows he will never regret. Jack is also biased toward the future, and not biased toward the near. Jack knows he is biased toward the future, so knows that if he schedules the meal for any day earlier than Sunday, then by Sunday he will regret having done so. He also knows that if he schedules the meal for Sunday, he will never regret having done so. So Jack schedules the meal on the last possible day, Sunday.

1. It is irrational for Jack to schedule the meal on Sunday.
2. If it is irrational for Jack to schedule the meal on Sunday, then either it is irrational for Jack to be biased toward the future, or it is irrational for Jack to be a regret-avoider, or it is irrational for Jack to fail to be biased toward the near.
3. It is not irrational for Jack to be a regret-avoider.
4. It is not irrational for Jack to fail to be biased toward the near.
5. Therefore, it is irrational for jack to be biased toward the future.

Fine dining, unknown deadline. "Imagine that every day Jack is asked whether he would like to schedule the meal the following day. Since Jack knows that he will come to regret scheduling it, he chooses not to schedule it each time. If Jack is unlucky enough to live forever, he may find that he never has the meal."

1. It is irrational for Jack to never schedule the meal.
2. If it is irrational to never schedule the meal, then either it is irrational for Jack to be biased toward the future, or it is irrational for Jack to be a regret-avoider, or it is irrational for Jack to fail to be biased toward the near.
3. It is not irrational for Jack to be a regret-avoider.
4. It is not irrational for Jack to fail to be biased toward the near.
5. Therefore, it is irrational for jack to be biased toward the future.

Premise 2, re-written: If it is rational for Jack to be biased toward the future, to be a regret-avoider, and to fail to be biased toward the near, then it is rational for Jack to never schedule the meal.

Why believe this? In general: if it is rational to be a certain way, and anyone who was that way would, in circumstance X, choose course of action Y, then it is rational for someone who is that way to choose Y in X.