Meursault is often characterized as a man who makes no choices. Yet Meursault makes a single very important choice. What is it?

Perhaps Meursault's biggest conscious choice was to see his world in existentialist shades of grey. If he could have bought "existentialist grey" at the paint store, he would have. Mersault decided that his choices did not matter. He sees the universe unfolding as it will despite what he thinks, says, or does. This certainly ties into the themes of the irrationality of the universe and the absurdity of life.