One of the most deeply contemplated questions that philosophy has asked is where a person's identity comes from. Identity is truly the fundamental quality of a human being. A philosopher can immortalize himself by discovering a solid answer to the question. Many times, hypothetical situations or scenarios (some more realistic then others) are brought up to help prove or disprove a view. In some cases, they serve merely as "brain fuel". They help to promote constructive and profound thinking on the subject. The case of having one's body and brain completely replaced with different materials while maintaining the exact memories brings up some heated issues. .
In John Perry's "A Dialogue on Personal Identity and Immortality", Perry uses the characters Miller and Cohen to advance the point that the new being is the same person. They argue by way of the Memory Theory. Let's assume that I am an advocate of the Memory Theory temporarily. If I am ever in the situation described I will take the transporter because I believe that the person who survives will be me. This is true because I will have all of the same memories as I did before. The fact that my memories constitute my identity can be shown in several ways. First off, I have memories of myself that are completely unique from memories of other people. For instance, if I remember being on a roller coaster with a friend, I can remember the actual feelings of intense fear and exhilaration that I had during the ride. My memories of my friend, on the other hand, are much more impersonal. No matter how hard I try to anticipate his feelings and what it was like to be him at the time, my memories can go no further then to give me a picture of my friend being afraid and exhilarated. This shows the intimacy between the memories and myself. It is this "stream of consciousness" that forms an identity. The long history of memories and my intimate relationship with them make me who I am.