身体の死後に意識を存続させる試みについての哲学的考察

Abstract

We examine here the philosophical problems concerning the recent attempts in several scientific fields to preserve human consciousness even after bodily death. One such attempt is that of "cryonics, " which tries to realize "neuropreservation" by preserving human brains or bodies at an ultralow temperature using liquid nitrogen under the expectation of future resurrection. It is based on the thought that preserving a particular brain state preserves a particular conscious state, including a person's sense of being, or "I" as the subject who is eager to survive. Another typical attempt is to upload consciousness into a computer. We should question whether complete information about a person and their memory makes "I" and allows for a person to continue to live in the computer, or uploading that information does not actually preserve "I" and it disappears with the decomposition of the brain. The former concept represents the belief that conscious states are informational states. The latter is a classical materialistic viewpoint, which is the thought sustaining cryonics. Concerning informational preservation of "I", we examine the standpoint of "connectome" which regards the informational connections of neurons as "I". According to this viewpoint, if the information states or memory of "I" is preserved, "I" will be also preserved, regardless of the decomposition of brain and body. This preservation attempt is called "transhumanism" by Sebastian Seung. However, information does not seem as substantial as the human brain. Therefore, Seung claims that "information is the new soul." This standpoint aims at preserving "I, " which is eager to preserve its selfhood and therefore is enclosed in itself. However, is it possible to accomplish this aim of preserving "I" as an enclosed selfhood, if the "I" or the material brain state can be discarded and only the informational state is vital to this preservation? Because it is not until the selfish "I" is made to be disclosed and opened that sharing "my" memory or information with other computers or with other persons is carried out. Thus, this disclosure is indispensable to the uploading of "my" consciousness. If preserving "my" informational state is no less important than the preserving "I" itself, then "I" must transcend my closed selfhood. This result is different from Seung's purpose of "transhumanism, " which aims at the eternal preservation of "I" as selfhood. Thus, it is not until the initial motive of the preservation of "I" is sublimated that the purpose of that motive can be completed. Therefore, to complete this initial attempt to preserve "I", we need to be "trans" humans, literally.