Music theory knowledge
There very often seems to be a battle of arguments between different groups of composers whether one should be well versed in music theory or not and both sides use self justifying arguments to prove their point. The important thing that is to know about music theory knowledge is that it is just a tool. Having a profound knowledge about music theory will not make you a better composer as not having it will not make you a worse composer. In fact developing an understanding of music that only lives in the traditional boundaries of music theory can prevent you from ever thinking outside the box while doing everything by feeling and ear can tremendously slow you down on things where people with good theoretic knowledge find a way in an instant. The ideal way to compose is to simply have the music flow out of you and simply write what you’re hearing in your head, subconsciously following the theory. To that point it doesn’t make much of a difference whether you know your theory and understand what you’re doing subconsciously or not. The one point where theory knowledge comes much in handy is when you reach a point where you’re getting stuck and don’t know how to continue your piece. In these cases falling back to the theory and simply knowing “theoretically I could go on like this or this or this or this, let me try what works best” will give you very often a very quick and effective way out while people without that knowledge need to struggle out of this blockage by using trial and error. So the bottom line is that knowing theory is quite important, helps you to get quicker and more effective results and gives you a fundament to communicate about music on a deeper level. However, if you have a strong musical imagination, theory doesn’t have that strong importance on composition as some academically trained know-it-alls like to make believe. Everybody has to find his/her own way to work most effectively and arrogance is never appropriate towards other composers, no matter which if the two sides you’re coming from.