I’ve been digging up a lot of information online about classical composition, and came across this page collecting Brahms’ thoughts on the topic. A lot of it is music theory specific to the era — analysis of the sonata form or rules for modulation etc.. Then there’s a section on “inspiration and creativity” with material like…

All truly inspired ideas come from God, and the consciousness of being inspired by him. Your religiosity will make you more conscious and aware of that fact, and of the fact that God is nearer to you than the others in your craft, and that you can consort with him without fear.

Even if I wasn’t an atheist, I would balk at this blather since it takes credit away from me — the guy doing the work — and hands it over to God who is sitting around on a cloud all day.

It does get more interesting a few points down, however.

When the urge to compose is present, appeal directly to the Maker and ask him the three most important questions pertaining to our life here in this world — whence, wherefore, whither? This appeal will immediately manifest feelings of vibrations that will thrill your whole being. These are the Spirit illuminating the sole power within, and in this exalted state, you can clearly see what is obscure in your ordinary moods; then you feel capable of drawing inspiration from above, as Beethoven did.
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Most of the time you have to be or will be in a semi-trance condition to such results.
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The dreamlike state is like entering a trancelike condition — hovering between being asleep and awake, you are still conscious but right on the border of losing consciousness, and it is at such moments that inspired ideas come.

This does tie in with some thoughts I’ve been having about the “creative state.” I’ve earlier discussed my belief that when your brain is in a focused state, it’s actually “shutting down” unnecessary brain functions, and actually using less “brain resources.” And I agree, as Brahms states, that when you get that creative flow going, ideas just seemed to pour out of you. I obviously don’t think this is because you have some antenna to God, but I do think you’re tapping into some part of the subconscious which is always working out problems. Brahms was right that it’s a meditative or trance like state (many have commented on the fact that you seem especially creative right when you’re waking up.) Perhaps Brahms, while focusing on his religiosity, was clearing his mind of unnecessary brain activity, allowing the subconscious to bubble up to the surface. If I could develop a means to enter this state at will, I would truly be unstoppable, and the world would shake at my power.