Identity Theory Research Papers
Identity theory is one view of modern materialism that asserts that mind and matter, however capable of being logically distinguished are only different expressions of a single reality that is material; that every mental property is identical with some physical property. Identity theory is the position in the philosophy of mind which maintains that mental states and brain activities are identical, though viewed from two perspectives.
It is a form of monistic materialism in that it maintains that the mind is essentially material in nature and if it is such, it is an alternative to classical dualism which holds that minds and mental events are made of a spiritual substance which is distinct from one's material body. Identity theory dresses the following issues:
- The problem of distinguishing sameness from change, or unity from diversity;
- Identity theory is primarily examined in connection with personal identity, universals, and the law of identity in logic.
- In personal identity the concern has been to determine whether anything in the body or mind remains constant; philosophers have reached no general agreement on this point.
The term identity has also become increasingly important in modern psychology. It has bee used to designate a sense of self that develops in the course of a man's life and that both relates him to and sets him apart from his social milieu. Identity theory addresses the short comings of behaviorism, which maintains that mental terms designate dispositions to behave in certain ways. The key difference is that behaviorism denies mental states and focuses instead on only observable behavior. Furthermore, whereas behaviorism is usually seen as a semantic theory about the meaning of terms, identity theory is a scientific claim about mental states and brain activities themselves.
Eliminative materialism can be objected to for several reasons. It takes the position that folk psychology is a false theory and that corresponding notions such as belief, experience, and sensation are fundamentally mistaken. Because it advocates the elimination of concepts that are embraced such as belief, dreams, and desires, one might be lead to endorse the more subjective viewpoint of folk psychology. Many philosophers, particularly functionalists, object to eliminating the categories of belief and desire from our conceptual landscape.
- First, they argue that folk psychology is a normative theory, about how we ought rationally to think and act. This normative feature of folk psychology is indispensable, since we cannot do without a method for criticizing and improving our thinking and reasoning.
- Secondly, functionalists point out that that folk psychology is useful for characterizing our mental states in a way that does not depend on their underlying physical constitution.
The argument made by the identity theorist is that mental and physical states and the experiences of both are connected. The mental experience, or the mind experience cannot be eliminated to leave only the physical state. In other words, it acknowledges mental states but identifies them with brain activity. In contrast, the arguments made by the eliminative materialist are that cognitive scientists should eliminate the phenomena of beliefs, desires, dreams, etc. from consideration in developing a theoretical account of the mind. On the other hand, it could also mean that we should eliminate the conceptual framework of propositional attitudes from cognitive science and use some other conceptual framework to account for the range of phenomena in question. On this view, the range of phenomena is not eliminated, but rather the way of conceiving that phenomena.
One possible argument against the identity theory is Leibniz's law of identity. This law states that two things are identical only if they have all properties in common. Accordingly, many criticisms of identity theory follow Leibniz's law. One example criticism against identity theory is that mental events and brain activity are not identical since we know some things about the one, but not about the other. For example, one can experience the recollection of memories and yet not know where memories are stored in the brain. This kind of equal knowledge is not required for identity. Another example, we can safely say that the vice president of the United States and the president of the U.S. Senate both denote the same thing. However, we may know some things about the role of the vice president, but nothing of the role of the president of the Senate.
Perhaps the most common criticism of identity theory is that mental descriptions and material descriptions are not identical since there are still the three points which distinguish them: localizability in space, objective observability, and intentionality. That is that, by Leibniz's Law, properties asserted about one described term, for example “pain”, can also be asserted about another term, “C- fibers firing”. These features apply to only one of the descriptions and not the other. Brain processes are spatial events, in that they have location, but sensations are not spatial. The problem is that Leibniz's law does not permit the elimination of either of the descriptions. The rules of identity maintain that what is true of one side of the equation must be true of the other side. Therefore the two cannot be identical.
In response, identity theorists argue that these problems are linguistic inconveniences which can be remedied with new language conventions that will perhaps follow a spatial model.