Very excellent question ABodensohn !

I don't think the same as my friends here. Because composition is nothing subjective, it's a set of rule you are following or not. These rules are well defined from early Greek and Egyptian antiquity period of History. Before 3rd were the Gold Point, base of many thing. But this is not the most important.
Today, the problem is many person are confused between self-feeling & good picture.
When you like a picture, may be the picture is not good technically. And sometimes, you don't like a picture, but it's very good technically and may be artistically.
Bonker was talking about Picasso. A great master, yes but.. Who really like Guernica at the very first look ? Who like 'les demoiselles d'avignon' ? Do you like Cezanne ? Are you sure ? I can show you many works from him you will not like. You eye will not like it the first time. But after studying the picture, looking and looking again. Trying to understand what he was trying to say.. may be you will like it... or not ! of course !
So, make the difference between 'i like it' and 'It's a good work'.
When you respect the rules, the eye will appreciate the result. Diagonal, triangle, cross, tiers, gp, spiral, and many others give structure to the picture, so your eye can feel it and follow a way.
Crtitics said that Real Master can break the rules.. so why follow the rules of a good composition then ? :oP
Try to be objective, while understanding a good/bad compo. After that, our heart can appreciate or not what we are viewing.
In Art School, under the course 'esthetic', we learn how to 'decompose' a picture with class of word like line, curve, dynamic, colors, balance, base (and some others). This interesting because you must observe and dissect the picture BEFORE trying to understand it. Like this you really forget the 'i like it, i don't like it' system.

So this is composition : the structure of the picture, the dark and Cartesian part of the picture.

In my humble opinion of course ;o) I hope it was not too long !!!!!

Good night, i'm going to bed now lolllllllllllll
Olivier**
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