[KeithT]

Personally, my thoughts are: if you need to ask why a photographer took an image, then the photographer has either failed to convey the message visually (if indeed there is a message), or the viewer is looking for something that isn't there in the first place. Most photographers take pictures to satisfy an artistic need in themselves. A lot of professional photographers take pictures to satisfy the needs of a certain publication they wish to sell to. As for any philosophy behind a photograph or piece of art, that is often considered as an important aspect by the viewer and not usually the photographer or artist. Like all published art critique, photographic or otherwise, it often borders on the metaphysical and the one who delivers it often waffles on with an impressive vocabulary that really means sod all to most of us at the end of the day. If someone gets a philosophical moment from any of my pictures, then good luck; but don't expect me to have any idea of what it is you are talking about.

EDIT: Henry Cartier Bresson was trained as a portrait painter. His training shines through in his photography. He was concerned more about composition and the way that the elements of a picture come together to make a pleasing and interesting image than he was about any philosophy behind it. At the other end of the scale, Robert Capa, took images of war because he was a war correspondent, no more than that. Certainly not because he was trying to make a philosophical point.