Music is science.
It is exact and specific. A conductor's full score is a chart: a graph which indicates frequencies, intensities, volume changes, melody, and harmony all at once, and with the most exact control of time.
Music is mathematical.
It is rhythmically based on the subdivisions of time into fractions which must be performed, not worked out on paper.
Music is a foreign language.
Most of the terms are in Italian, German, or French; and the notation is certainly not English - but a highly developed kind of shorthand that uses symbols to represent ideas. The semantics of music is the most complete and universal language.
Music is history.
Music usually reflects the environment and times of its creations, often even the country and/ or community feeling.
Music is physical education.
It requires fantastic coordination of finger, hands, arms, lip, cheek, and facial muscles, in addition to extraordinary control of the diaphragmatic, back, stomach, and chest muscles, which respond instantly to the sound the ear hears and the mind interprets.
Music is all of these things, but most of all...
Music is art.
It allows a human being to take all these dry, technically boring (but difficult) techniques and use them to create emotion. That is one thing science cannot duplicate: humanism, feeling, emotion, call it what you will.