I'll start out by saying that yes, every composer has been influenced by other composers. Whether they realized it or not.
My dilemma is, where exactly would the line between plagiarism and having been purely inspired and therefore influenced by someone, go?
Of course, there's no copyright to C major scale, but if one is improvising on C major, he's destined to encounter some patterns that have already been used, possibly over and over again in different contexts.
If one has listened to a lot of music, and been inspired by it, is it possible that certain patterns of music become concepts of feelings? When you're improvising, you're listening to these feelings, and your mind articulates them into these patterns, leaving you as a mere data *transferring* unit.
This reminds me of ummm... Alfred Brendel saying something about "mastering the score's details in order to be free" (I read it on another thread, not sure about the content). Do we have to hear all music in the world to be free of being mere plagiators? Or is there only space for certain amount of music to exist and affect our feelings simultaneously, at time, and depending on what our inner world is going through, we build this "repertoire" from among all the music we've ever heard, and use it as a vocabulary to articulate our feelings?
If you realize you're using an already existing pattern, and can immediately point out the most probable source of it, do you still not hesitate to use it in your music? It of course depends on the "context" of the musical thought, but what is the scope of the scale we observe as a "context" each time? Will we think of that particular pattern as an independent musical thought, or is it one beat, or a passage, or the movement in whole?
How do I know I'm creating something new and not just building variations of the old? Do I just have to become self-conscious enough to judge this by the structure of the composition; from where did it arrive to this particular point, to where is it going to lead, what is the exact role of these notes regarding the whole...
This dilemma is actually quite depressing because it again reminds me of the setting that our humans' minds are only mirrors that reflect the external world. No matter what the complexity of the positions or the number of mirrors is, it does disturb me to feel like a plain gathering point of external signals.
On a more pragmatic note, where does everyone consider the line goes, or what do you do when you realize you've possibly been subliminally, unconsciously "copy-pasteing" melody? Do you keep going and accept it as it is - a significant part of your composition - or abandon it and try to find another route for writing your feelings on paper?