haha, you dont even know what you're talking about
what do you think abstract is? it IS lines and colours.
it can either be a perception of reality, or, something, that expresses the way one feels.
Like it or not, any form of expression put into pictorial form, is art, thus, is art. I could've done a lame cartoon sig and stolen other peoples art, or, i could've made a lovely little scene with happy children playing in the grass; but thats not how i felt at the time, thus, thats not what it is.
simple as that