In his “Essay on Human Understanding,” John Locke discusses personal identity trying to show that personal identity depends on our memories. Locke also discusses some of the possible changes in our constitution that still result in the same personal identity. However, I think Locke fails to account for some aspects of memory that affect personal identity, which leads me to think that personal identity may not be what Locke proposes. Locke distinguishes three types of substances: God, finite intelligences and bodies. God is infinite and his identity cannot be doubted, while finite intelligences have their own beginning of existence as identity, for example souls. (Essay II.xxvii.2) By identity, Locke means being able to differentiate between things, however similar, that exist at the same time. (Essay II.xxvii.1) Bodies have the same identity as long as there is no addition or subtraction of particles of matter. (Essay II.xxvii.3) Organisms such as animals can be identified through the continued existence of the same life with changing particles of matter organized to meet the needs of that life. (Essay II.xxvii.5) Locke believes that this is where the identity of man also lies, he states, “…the identity of the same man consists in the continuation of the same continued life… organized in a vital way for the same organized body. (Essay II.xxvii.6) Locke then differentiates between what a person is and what a man is. For Locke, a person is a being who can think, is intelligent and knows that he can think, “…an intelligent and thinking being, who has reason and reflection, and can consider himself as himself…” (Essay II. xxvii.9) Personal identity , moreover, it depends on the awareness of the step...... middle of paper......personal identity is also not real. This leads me to think that Locke's theory does not take into account the possibility of false memories. Furthermore, we now know that our memories are not perfect, as Locke perceived them, I think. For example, eyewitnesses have been known to misremember events. Since our memories are not always perfect, personal identity may depend on something else. Locke offered some excellent ideas regarding understanding personal identity. The concept of a man and how it is different from a person helps to understand many scenarios such as: two people switching bodies or a person switching bodies with an animal. Locke's ideas about two souls being able to be the same person or one soul being different people are also very interesting. However, I do not entirely agree with some aspects of Locke's theory of memory..