Completely with you, Sarah, concerning the "relationship between sound/ear and emotions" and I wish to particularly focus in on your use of "why music moves us so deeply." To pick up on an earlier post that involved the French term sens with 'directionality': the movements of mind/body/imagination/emotions/etc. in ways that are not wholly predictable, controllable, explainable, comprehensible -- how sound (not just 'music') can get so directly on to our nervous system, into our veins and brain stem, our entire physiology, affect our biochemistry so intensely and subtly (pharmaceutically?), without necessarily going through any form of narrativity or conceptualization, let alone other gradients of linguality. I feel I carry around sounds far more powerfully and with greater longevity than any lingual sign or form of signification.
On a completely different track concerning reason and its relation to human emotion and action, a Foucauldian intervention:
“All human behavior is scheduled and programmed through rationality. There is a logic of institutions and in behavior and in political relations. In even the most violent ones there is a rationality. What is most dangerous in violence is its rationality. Of course, violence itself is terrible. But the deepest root of violence and its permanence come out of the form of the rationality we use. The idea had been that if we live in the world of reason, we can get rid of violence. This is quite wrong. Between violence and rationality there is no incompatibility.”