Well, although that may be true, you must take into account that this is philosophy, and although philosophy and science are sisters, they differ. Philosophy takes into account logical justifications provided they are valid and sound according to the premises. However, Behavorism here isn't so much just the psychological babble...although it is one of the reasons behavorism exists as a philosophical concept.

There have been arguments for centuries concerning "inner knowledge" (for lack of a better phrase...which IS NOT instinct). The idea of the subjectivity of the mind, of the self, of some sort of predesigned filing system for empiricism, is something many philosophers and psychologists want to fully understand. Behaviorism was indeed an interesting step in understanding that fuller. Although behaviorism is more or less a forgotten movement these days.

Anyway...emotions may not be external, but that does not mean the external does not coincide with emotions. The real problem here is that there really hasn't been an emotional-philosophy to come about just yet. And although it's a topic I'm extremely interested in, I myself don't know what possibilities this philosophy leads to. As far as I've encountered thus far, is that emotions might in fact be the bridge between mind and body...that is, of course, if you're a dualist of sorts.