William James discussed the connection between attention and mental processes, "Millions of items…are present to my senses which never properly enter my experience. Why? Because they have no interest for me. My experience is what I agree to attend to…Everyone knows what attention is. It is the taking possession by the mind, in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thought…. It implies withdrawal from some things in order to deal effectively with others."