Yes I do not negate that microtonal has interesting effects. The question was why there a 12 tones in western music. And the answer is that minor 2nd is the sma

Yes I do not negate that microtonal has interesting effects. The question was why there a 12 tones in western music. And the answer is that minor 2nd is the smallest interval you can separate when played together. I should have been more precise in my initial comment.