Michael Mitchell: Archive

It's neither. Emotions are neither rational nor irrational.

Perception > Identification > Evaluation > Emotion

It all happens seemingly instantaneously, but rationality only applies to the identification and evaluation parts of the process, and then emotions automatically sum that shit up. If you're rational, then you'll be able to consistently identify your emotional states, and since you'll most likely be successful at goal achievement, you can expect them to be pleasant, but regardless of their nature -- positive or negative -- they can never function as guides. They can indicate whether or not you're fucking up, but they can't tell you how to correct your mistakes or better achieve your interests.