I disagree w/that. Moods are not (necessarily) irrational. They're biological responses. Now, moods can certainly lead to irrational behavior, I'll give you that. But a strong rational mind can feel deeply but still make logical decisions...
Feelings aren't irrational. What we choose to do with them can be.
I love the massive scope of the implicit question behind these statements: "are feelings rational or not?". It's OT, but since it's your thread anyway...
I hadn't thought about it heavily before I posted, but your angle on it is interesting. I automatically/intuitively categorised emotions as irrational, but your separation of emotion from causal effect is challenging that assumption, so now I'm wondering what - if any - intellectual justification I have for my intuition.
I think it would be this:
I certainly agree that one can choose how to respond to an emotion. No question about that.
The underlying question we differ on is whether a mood is "a biological response" and whether that makes it free of irrationality or not.
Clearly, in the sense that it is generated internally, in response to a set of external stimuli, it is biological in origin. But I would suggest that it is not free of irrationality, because mood does not arise in a simple direct causal relationship to external stimuli. There is a cognitive aspect to perception that modifies the raw "real" aspects to external stimuli and it is our perception of reality that drives our moods. The same set of external stimuli can result in very different perceptions, and moods, some of which are rational and some which are not.
For instance, the classic "illusion" of perceiving a bush in the wind when walking home tired at night as a possible mugger, whereas in the daytime you'd see it as the bush it is. Same basic stimuli, diffent perception, and due to the different cognitive/emotional mindset at time of the perception, a different mood that results.
From that it follows that mood and the emotions that result are driven partially by the pre-existing mindset at time of experiencing the mood. Since that includes potentially irrational thoughts, the mood/emotions are themselves susceptible to being "contaminated" by irrationality.
They don't
have to be so, but they are almost certain to be so, because our cognitive processes are heuristic rather algorithmic in nature. Heuristics use intuition, and intuition can be irrational.