Most western philosophers have been content with a dualism between, on the one hand, the subject of experience, and on the other hand the world, the objects of experience. However, this dualism contains a trap, since it can easily seem impossible to give any coherent account of the relation between the two. This has been a permanent motivation towards either idealism, which brings objects back into the mind of the subject, or some kind of materialism which sees the subject as little more than one object among others. Other options include neutral monism.