Memory Theory of Personal Identity

Memory Theory of Personal Identity

Locke's theory of personal identity entails the memory theory. According to Locke, the basic idea behind personality theory is that no two similar things can co-exist in the same spatial environment. In terms of personality then, each person has a spatio-temporal history, embedded in memory, that is unique within the environment that is occupied together with others.

Locke's view is closely intertwined with his views on religion. God is a being that exists unchanged and simultaneously in both spatial and temporal environments. Thus the memory theory of personal identity is not applicable to him, as he is infinite and unchanging. Finite beings on the other hand change and are changed by their environment. They are the sum of their unique experiences as they move through space and time to their end. As such then each finite being exists as distinct from other finite beings - hence the uniqueness of each. Each such being then occupies a space that is unique while coexisting with others of its sort.

Locke describes the identity of an individual human being as being rooted not in their rationality, nor by the presumed soul within each. Instead, this identity is to be defined as a living animal within a specific species, which has a number of particular defining characteristics.

Locke thus defines a human being in terms of function rather than underlying nature. The identity of a conscious person then is independent of the substance or substances composing the person at any time. Moral reasoning is somewhat simplified by this view, as morality is independent of personal identity. Thus moral accountability becomes a question not of personal identity, but another issue altogether.

The memory theory thus simplifies questions of morality, as memory is supposed to compose the personal identity, which should have no problem relying on its past to adhere to morals in the present and the future.

Bundle Theory

Hume, in contrast to Locke, saw personal identity as part of a greater whole, where all aspects of humanity are integrated with the personality itself. Personal identity, according to Hume is then a succession of perceptions, which changes and grows as the human being moves through life. Thus it is not a static set of characteristics, whereas Locke's theory presupposes a basic, unchanging set of attributes regardless of surface change and growth.

Hume refers to these changes as a succession of perceptions that change as human beings grow and develop. Thus, as physical growth occurs, so does perception. The personal identity is thus closely related to this succession of perceptions. According to this then the personality of the person as a child is not the same as that of the same person at twenty years of age or indeed in old age. In this way then the personal identity is variable, which contrasts with Locke's view of identity as static. According to Hume, the variables inherent in identity should also be seen in their relation to the whole in order to determine the personality as a whole.

Hume also addresses the issue of rapid vs. gradual change. If any part of the body or personality changes suddenly, so does the perceived identity change rapidly. However, the same is not true of gradual change, for example as happens in terms of physical and spiritual growth. This then could be the reason for Locke's separation of the physical identity from all other aspects of humanity: the change perceived in a growing person is too slow in succession to perceive any great change and thus the assumption is that the basic attribute set remains unchanged. This is what Hume describes as continued perception of gradual change, creating the illusion that the identity is static. This, according to the philosopher, accounts for the fact that a person, animal or plant grows and changes without losing their fundamental personal identity, although the body is entirely changed.

Split-brain Cases as treated by Bundle Theorists

Bundle Theory, as seen above, holds that the unit of consciousness can be explained not as a single individual person but rather as a series of states and events within the mental world of each person. Every aspect of personhood is thus integrated, and cannot be separated from each other. Personality theories are particularly interesting when applied to cases such as split-brain patients.

In split-brain patients, there is no dominant hemisphere, with only the sub-dominant halves remaining. In these cases, there is no connection between the two halves of the brain, each perceiving the world according to its own field of perception. Bundle theorists then argue for the integration of the variety of experiences in a unified person, although these experiences are diverse.

The theory can then be likened to a person having several diverse experiences at the same time, which is the case for most persons going through life at any particular time. In the case of a split-brain patient, several states of awareness of several different experiences occur, according to bundle theorists. There is no third, separate entity as might be assumed by memory and ego theorists. The entire experience occurs within the person, and the person remains an individual, although the experiences and awarenesses within the same person are diverse and numerous.

Evaluation

Memory theorists are essentially attempting to separate the personal identity from everything else, including morality and experience. Identity is assumed to be made up of a number of essentially physical parts that remain the same in essence throughout life. This has been shown by study and experience to be incorrect. There are many variables within the individual, even in terms of physical properties. As Hume points out, growth occurs both in the personality and the physiology of a person. The fact that the identity does not change is explained by the gradual process of growth. This may then also be what led to Locke's memory theory that separates the physical aspect from all other experiences of humanity.

Locke's theory is however not very effective in terms of personal identity, because it is so easy to disprove. Human beings are integrate parts forming a whole within themselves and as part of a community. To separate any of the parts from each other is to deny the very nature of humanity. Hume on the other hand assumes both integration and a dynamic process of experiences in terms of the identity and personality.