Those parts of brains hardly act intelligently on such preferences. They are unable to use long-term or complex plans. They are also time inconsistent, which doesn’t make them irrational* but does make them bad trading partners.
*Rational time inconsistent agents would self-modify to be time consistent, but humans have limited self-modification abilities. The fact that the unconscious does not try to improve its ability to self-modify is one piece of evidence of its irrationality.
Those parts of brains hardly act intelligently on such preferences. They are unable to use long-term or complex plans. They are also time inconsistent, which doesn’t make them irrational* but does make them bad trading partners.
*Rational time inconsistent agents would self-modify to be time consistent, but humans have limited self-modification abilities. The fact that the unconscious does not try to improve its ability to self-modify is one piece of evidence of its irrationality.