It was rational because you valued what your teachers and parents thought. All value is subjective, so you cannot define a universal optimum.<p>To say whether something was a rational decision requires evaluating the subject&#x27;s utility function at the time of the decision. This is something only the subject can do. Trying to judge something after the fact is very difficult.<p>What good input could you have used when you made the decision (or while you continued to execute it)?<p>Making mistakes in reasoning and&#x2F;or lacking information that would allow for making a decision at a higher perceived utility does not make one irrational.<p>An irrational decision is one where an action determined to have the most utility is not taken.