The mind (adjective form: mental) is that which thinks, imagines, remembers, wills, and senses, or is the set of faculties responsible for such phenomena. The mind is also associated with experiencing perception, pleasure and pain, belief, desire, intention, and emotion. The mind can include conscious and non-conscious states as well as sensory and non-sensory experiences. The exact nature of the mind is disputed. Traditionally, minds were understood as substances, but contemporary philosophers tend to see them as collections of properties or capacities. There is a lengthy tradition in philosophy, religion, psychology, and cognitive science exploring what constitutes a mind, what its distinguishing properties are, and whether humans are the only beings that have minds. Mind, or mentality, is usually contrasted with body, matter, or physicality. The issue of the nature of this contrast and specifically the relation between mind and brain is called the mind–body problem. Traditional viewpoints included dualism and idealism, which consider the mind to be non-physical. Modern views often center around physicalism and functionalism, which hold that the mind is roughly identical with the brain or reducible to physical phenomena such as neuronal activity, though dualism and idealism continue to have many supporters. Another question concerns which types of beings are capable of having minds. For example, whether mind is exclusive to humans, possessed also by some or all animals, by all living things, whether it is a strictly definable characteristic at all, or whether mind can also be a property of some types of human-made machines. Different cultural and religious traditions often use different concepts of mind, resulting in different answers to these questions. Some see mind as a property exclusive to humans, whereas others ascribe properties of mind to non-living entities (e.g., panpsychism and animism), to animals, and to deities.