Sunday, March 2, 2008

It’s Not Easy Being Rational

If you’ve ever met a disguised anti-rationalist you’ve probably heard the “but it’s rational to be irrational” line. They believe themselves to be clever in finding the rationalist’s loop hole in being irrational. For instance, ‘irrationally’ going on a shopping spree once a month should be deemed a rational act. Clearly, it is easy to point out how such a proposition has no merit. For one, it posits the definition of ‘rational’ to mean the same thing as it’s opposite. These fundamental problems, however, only transpire when you interpret the proposition literally and not for its implicit message.

Saying that a shopping spree is rational and irrational at the same time implies two things about a person 1) their arrogance in throwing around intellectual words they don’t understand 2) the satisfaction and non-regret they get from having a shopping spree once a month. If the former wasn’t the case, the person would understand their once a month shopping spree was never irrational to begin with.

Assigning value to something, and therefore creating a utility function, is not where irrationality is committed. For example, preferring your coffee with two spoons of sugar is just as rational as preferring it with ten. You only act irrationally if behave contrary to your preferences/utility function. A trivial example is if you knowingly added no sugar in your coffee when in the past you’ve always preferred at least one spoonful. For a non-trivial example see Allais Paradox.

You might be thinking to yourself, “If behaving rationally only requires me to do what I want, I must be pretty damn rational.” This reasoning depends on a flawed assumption that you know what you want. If you’ve ever experienced regret or remorse, one of your past actions/choices contradicted your original utility function. These emotions serve as a nice defense mechanism against irrationality because they make us think harder before acting. (Obviously, if you prefer to stray from regret and remorse then you’ll think twice before acting). Unfortunately, not all of us possess such an accurate defense mechanism and therefore must think harder whether or not we believe regret might supervene on our decisions.

5 comments:

Ben K said...

See here for a discussion of rational irrationality.
Also, your Allais paradox link is improperly formatted.

Unknown said...

Acting rationally depends on the perception of what is rational. If I perceive a shopping spree as maximizing my utility, then it is a perfectly rational act. However, if you believe, due to my shaky financial situation, that going on a shopping spree is irrational, then you are testing your perception of what a rational act is against my perception of the same thing. So, the rationality argument can be used for and against any argument depending on initial conditions and each persons utility function.

Stating that feeling regret or remorse for your actions does not indicate you have evaluated your utility function incorrectly. Although perfect information is a general assumption for lower level economics, see Stiglitz et al. (Nobel prize winning paper) on the impact of asymmetric information on markets. Otherwise, simple common sense tells us that we can never know everything relevant to our decisions at the moment we need to make them. Furthermore, even if we did know everything, we would need to prove that the universe is deterministic in bringing us the desired outcome.

Lior Gotesman said...

Ben,

Fixed and I'll check it out

Sean,

From what you say in your first paragraph I can conclude that we are in agreement. Like I send in the original post, going on the shopping spree is a rational act if you deem it so. Acting irrationally only occurs when you knowingly don't do what you think is rational.

I made an implicit assumption about regret and remorse. I assumed that they only occur when the subject knows that in the past they had knowledge (or access to that knowledge) of the consequences of their actions, but choose the wrong action. If you don't agree with this assumption, I would say that your definition of regret is blurred with disappointment.

If the knowledge of what actions bring about desired outcomes is not accessible, I don't see how one would feel regret and not disappointment.

Unknown said...

a3dfx,

I guess the issue comes down to whether or not we can ever act irrationally. Lets have a look at what it means to act rationally first.

We are constantly presented with choices. In order to act purely rationally, at each individual moment we must choose the action available to us that maximizes our utility function. As a basic definition of rationality, this is probably something we can agree on.

So the question becomes, how do we know which choice will maximize this function? As we each determine our own utility function, and by doing so set its conditions for maximization based on the potential choices offered, the choices which are eventually picked will automatically maximize the perceived utility function. Therefore, this would fit the definition of a rational act.

Utility functions change over time. As new options become available, the choices that maximize the new utility function inevitably change. However, despite these changes we are still constrained by rationality and our own perception of our new utility function. Therefore pick the new perceived utility maximizers.

So, we always pick the rational choice because we set the conditions of the function. By definition, acting irrationally is impossible. Regret or remorse is a current perception of a perceived irrational act in the past based on an evaluation of present circumstances. However, as this does not change the conditions that led to the precious choice, it cannot have been an irrational choice.

Regret and remorse could also be a comparison between real choices offered by your current utility function, and an unattainable utility point on another function entirely. Whether this other utility function was attainable if you had made different choices at some point in the past or not makes no difference to the rationality of an act.

We must always know what we want at every moment. If we cant know it, we cant want it. If we can't want it at the time when we need to decide what we want, it can't enter our calculations of the rationality of an act.

Lior Gotesman said...

Being a rational agent requires a purpose or direction. We have been discussing the purpose of maximizing utility. If you set up your utility function, at a given moment in time, you've created a theoretical set of actions that will lead you to maximizing your utility function. If you currently desire a coke from the fridge, there exists a set of actions which will satisfy this demand in the most desirable way.

It could be that on your way to your fridge you suddenly decide you hate fridges and want to break it. Again, there is a rational way of getting this done. The closer you are executing the theoretical optimal set of actions, the more rational you are (given you have run through all the consequential information you can attain).

You would be irrational if you didn't use all the knowledge available to you while assessing what actions you should take. For example, you know you have an ax in your garage, but decide to use your fists in breaking the fridge. You can also understand why you might feel regret of not using the ax as you sit in the hospital for your bloody fists.

Every time you change your utility function, you change your goal and therefore have a new set of actions which are deemed rational or not.

If never know what you want, no direction whatsoever, then you need not worry about being rational. Then again, I don't understand how long you'll last without food. My point is, there is always some goal you have and it is meaningful to say there are more rational people then others.