Personal Identity Theory For Locke And Descartes Philosophy Essay

Published: Last Edited:

This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.

Wherein does self exist? The question of self or personhood has held the minds of philosophers as far back as Plato. What, then, is the human sense of self, in so far as we understand it? This paper is will analyze the personal identity theory of Rene Descartes and John Locke in their respective discourses Meditations on First Philosophy and An Essay Concerning Human Understanding. Moreover it is the aim of the author not only to contrast their respective positions, but to argue the superiority of the Lockean account of identity over the Cartesian one. I begin by examining the two understandings of personal identity distinctively while minimally assessing necessary criticism of their views. I will then consider the superiority of Locke's view on personal identity in relation to his epistemic understanding.

Descartes' focus in Meditations is to re-evaluate the accepted scholastic system through a new epistemology rooted in doubt and scepticism. Nevertheless, Descartes does borrow from the scholastics in his understandings of God and reality; the distinction for him is the end not the means. If Descartes is associated with the divergence from Aristotelian-Scholastic thought than without a doubt Locke is the person associated with the departure from rationalism to empiricism. Before dealing with text I think it is necessary to place Descartes in his proper historical context. The preponderance of writing on the theory of personal identity in the past has been influenced by John Locke notwithstanding Descartes' understanding was a necessary departure from previously agreed upon philosophies. Descartes concept of substance is a variant of nominalism - which contrasted scholastic thought - whereby substance and accident are not distinct; this change would be fully realized in later epistemologies where thought is the foundation for knowledge.

Descartes' understanding of knowledge and of person is rooted in a methodological doubt. This doubt is based on withholding "assent no less carefully from opinions that are not completely certain and indubitable than I would from those that are patently false." The impartial nature of his doubt is the basis for his scepticism of "those principles which supported everything I once believed." After acquiescing that he can doubt his dreams it follows from his system that he must doubt his dreams. Additionally, despite being a mathematician, he argues that a person can doubt the objectivity of mathematics if God allowed an evil genius to deceive him. According to Descartes such an evil genius is as "clever and deceitful as he is powerful, who has directed his entire effort to misleading me." The objects of Descartes reality can be doubted ergo they must be disregarded before he can determine what can be known.

The second meditation lays the foundation for rationalism; the focus of Descartes' self-thought is no longer object of thought but the subject of thought. Moreover, his theory of personal identity - or more appropriately self-identity - is a necessary consequence of such self-thought. The famous cogito ergo sum is what neither a dream nor an evil genius can cause Descartes to doubt. The following statement, I am thinking therefore I exist, will be shown to pass the test of doubt, as follows:

I can doubt my senses because I could be dreaming

I can doubt the objectivity because of an Evil Genius

These two problems as well as the entire system of methodological doubt all presuppose one foundation: thought and self-existence. The cogito while the basis for an epistemology is a very loaded statement. Three propositions can be reasoned from the use of the word.

"I" exist

"Thought" exists

(2) is a resultant action of (1)

Descartes' realized understanding of a thing that thinks is that "a thing which thinks is a thing which doubts, understands [conceives], affirms, denies, which wills, refuses, imagines also, and perceives." This however is a very broad definition of thought. Descartes argues that thought is intimately connected with consciousness of the mind and the body. Descartes held the essence of body and mind to be extension and thought. Accordingly a thinking thing must be a conscious thing. While Descartes does not pontificate the details of such identity to the extent in which Locke does there is a very evident connection between his view of epistemology and identity.

In contrast to Descartes, Locke's theory of personal cannot be understand prima facie from his epistemic view, but nonetheless is a ground-breaking contribution to philosophy. His theory of personal identity not only addresses the sensory perception, but also the sensory reception of experience; the linear relation between the present awareness and a past memory is instrumental to his definition of a person. Furthermore, Locke's contributions to the theories of personal identity are as much ontological as they are ethical; his contributions are concerned with ethical nature of an individual as a moral agent.

While Locke's primary concern is contained in the second book of his discourse, without a doubt the first book addresses the necessary underlying problem, which is an innate idea. Locke argues that innate ideas do not exist nor are they necessary in a justification of knowledge. Locke's argument about identity, as well as an idea, is that they are too complex to be innate. The problems of identity which Locke addresses are ethical, spatial, and temporal; these issues are far from simple and at the root necessarily require knowledge viz. experience. Locke wrote that "our Idea of sameness is not so settled and clear, as to be thought innate in us."

Accordingly Locke argues that an idea is both received and perceived through experience spatially and temporally. It is not innate to the person, but experienced and recalled upon by the person between a temporal point in the past A and the present B. This idea is formed when "considering any thing as existing at any determin'd time and place, [and] we compare it with it self existing at another time." For Locke identity is concerned with existence over a period of time. Moreover existence of something is broken into three broader categories: inert objects, living things and persons. The identity for something such as humans, trees, and rocks are respectively different. While a rock exists is a combined set of atoms it will remain a rock. Yet if I were to crush the rock it would result in several smaller pebbles forming. In the same way a glass of water contains a set number of atoms, if I pour the water out of the cup the continuity of its identity is separated into smaller droplets. On the other hand a tree has a dynamic identity; for instance, an acorn while having a very distinct identity, changes, and grows until it reaches the life stage of an oak tree, which will age, die and rot. The identity of a tree is less concerned with the composition, but more the organization. In accordance with this Locke writes:

if two or more Atoms be joined together into the same Mass, every one of those Atoms will be the same, by the foregoing Rule: And whilst they exist united together, the Mass, consisting of the same Atoms, must be the same Mass, or the same Body, let the parts be ever so differently jumbled.

In contrast to an inert object, Locke writes the following concerning living things:

being at any one instant in any one Collection of Matter, is in that particular concrete distinguished from all other, and is that individual life, which existing constantly from that moment both forwards and backwards in the same continuity of insensibly organized Parts united to the living Body of the Plant.

We can see clearly a distinction between an inert object and a living thing. This however does not address the third category which is the nature of a person and the identity therein constitutes a living thinking thing.

While the second definition is clear and concise enough to describe a human being it does not describe a person according to Locke. For Locke experience, memory and consciousness are intrinsically linked with his definition of a person. It is the relational existence of memory from A to B that defines personhood. For this reason he writes that "it being one thing to be the same Substance, another the same Man, and a third the same Person." Locke designates this distinguishing criterion and thus a human is "nothing but a participation in the same life … in succession to the same organized body" (2.27.6). It is not the ration of a reasonable thinking thing that makes someone human, but in addition the constitution of a being between temporal point A and point B.

Without a doubt Locke is in complete agreement with Descartes that the ability to reason one's own existence is linked with person-hood. A person must be able to think, reflect, and be self-aware, but these are not innate concepts. This is where Locke diverges from Descartes; a person is defined as "the same thinking thing in different times and places." For Locke a person is only a person as far back as they can remember. This raises another question regarding gaps in memory and personhood. If I cannot remember certain events of my past perfectly, is my identity as a person in question? As a living thing my material organization can provide continuity between myself at age three and age twenty-five, but can my identity as a person provide such continuity? Locke does not consider such gaps to be a necessary problem and does not provide much answer in Essay, but he does address the concerns to his critics. As a consequence for Locke the continuity of person is the awareness of thought in the present and the conscious memory of thought from the past. Hence, a person is in a very broad sense human. In a narrow and defined sense a person is a being which is self-aware and perceptive of the present, but more importantly receptive of a past date and place.

I have thus far explained in small length the positions that Locke and Descartes hold with regard to identity. The next task will be to show the strengths of the Lockean position over and against that of Descartes. The first point I want to make is that Locke writes extensively in chapter XVII of his second book whereas the Cartesian understanding of self is rather simplistic. For the Cartesian self is contained in the simple, albeit loaded, word cogito. Self is contained in the consciousness and this is part of the mind-body dualism; the body cannot think apart from the consciousness of a thinking mind; these linked substances make up self. But the problem with this statement is that it does not take into account the need to be self-aware which Locke addresses. Where Descartes starts Locke finishes. Locke agrees that a thinking thing is necessary for personhood, but it is not merely the ability to think or reason, but to understand. It is necessary for the Lockean understanding of a person to be self-aware, thinking, and perceiving of the moment and the past. It is the introduction of a temporal variable where Locke diverges greatly from Descartes who is concerned with innate ideas and he is able to address the issue from experience.

One problem I perceived and which has been addressed by other critics is the issue of gaps in memory. If I can remember being a child at the age of ten, but not at the age of three, does my personhood start at ten? One common way of answering this problem is by applying a transitive relation for a person. For example the lapsed memory could be looked at in the following way:

I remember being ten years old at the age of twenty-five

At the age of ten I remember being three years old.

I am three years old

Even though at the age of twenty-five I do not remember being three years old it follows that if there is a transitive relation between A and C. If A is equal to B and B is equal to C than certainly this relationship follows that A is also equal to C even with the lapse in memory. Thus the problem of memory is not as important as Locke claims. It is arguably clear that Descartes offers a primitive understanding of self, albeit not his full concern in Meditations, but Locke provides what is necessary for a realized understanding of reality, knowledge and self through the perceptive and receptive mind.

In brief, thus far, we have seen an account of Descartes and Locke in their respective understandings of self as expressed through their epistemic models. And while Descartes offers a truth which is apparent, it is not as innate idea as he hopes to express. Without features such as perceiving and receiving sensory experience in variables such as time and space, we are left with a momentary understanding of self. Locke provides what is necessary, albeit with some problems, to understand self properly through an empirical epistemology. His theory provides the necessary answers to serious ethical concerns which we are dealing with today and thus it is no surprise that his influence affects modern theorists.