Metaphysics: presentations

Below are a few of the handouts written by individual students for presentations in an undergraduate-level metaphysics class. In each presentation a particular philosophy paper related to class was introduced; a reconstruction of its argument was analysed; some questions and comments were raised by the peers and the professor. I did not take notes to cover all the discussion, so this could serve only a partial role in reflecting the class or the presentation.

Presentation on personal identity

1. Biological view of personal identity 14 HQY Eric Olsen, Was I ever a fetus.

Fetus case;embryologists tell us that a human fetus that is less than six months old cannot remember or experience anything, and thus has no mental capacities worthy of the name.

2.The only sound solutions: biological view
A
We persist, as other animals do, just in case our biological lives continue.
B
At any point in my career I survive iff my vital functions_those complex biochemical and mechanical activities of my atoms by virtue of which they compose a living organism- are preserved.
C
The biological view does not entail that I came into existence at conception. Activities mus be coodinated.
3.
Two objections:
First,
a person is not numerically with a fetus.
Secondly,
the fetus survived but never came to be a person: it merely came to share its matter with a person numerically different from it.

The reply to the “transplant”.

My criticism: It might be good to see how can biological description and theory could go WITHOUT a pre-concept of individual. I doubt that is ever possible.

Presentation on personal identity
A solution to the paradox of fission 13 WSM
Douglas Ehring ,1986. “Personal identity and time travel”
Mark Moyer, 2007, “A survival guide to fission”

1. The case of Ronald Reagan indicates our intuition that the duplication people are two in number, not one.
2. To solve the paradox of fission, we should reject our common sense intuitions. Here are some solutions to the paradox of fission: Chrisholm: Reagan survives as one of the two later people, though we simply don;t know which of the two he is. Lewis: Reagan is in fact two people. Ehring: Reagan-B and Reagan-C are one person. Parfit:Reagan ceases to exist, so he will later be neither Reagan_b or a. Johnston: There is no fact of the matter about personal identity, for our concept does not apply in such bizarre cases of fission. 3.Ehring’s solution: Three typical characteristics as evidences for thinking that there exists more than one person in the post-duplication situation: The lack of shared consciousness The lack of common body The causal independence Point:None of theses characteristics require the existence of more than one person. Strategy: introduce cases which share the proposed characteristics but fail to involve more than one person. 4.Divided consciousness and multiple bodies: The case to show the extended failure of shared consciousness and multiple simultaneous body stages can be compatible with the existence of a single person: The case of time travel into the past (Jones is the time traveler) Absurd consequences; Solution to the consequences: person stages

5.Physical -causal independence
There is a difference between the time travel case and the duplication example:Jones-34 is P-related to Jones-4 but Reagan_C is not P-related to Reagan-B
However, being P-related is not necessary for being stages of the same person.
The case to show that person stages which are not P-related are stages of the same person: The case of pre-cognition.
The stages of Person-C at the level of his mental life, bear a relation to the experiences of person-B which is similar to the relation we bear to our past selves.
Objection: pre-cognition is not the same as memory
Response:Consider the case of Smith.

Presentation on personal identity
Transworld identity or worldboud individuals? srx

1. Transworld identity.
   Chishom: We start with Adam, say; we alter his description slightly and allow him to live for 931 years instead of for only 930"
   How could Adam (lives for 931 years) be identical with that one(lives for just 930 years)
   2.Lewis’s objection on Transworld identity:
   1) worldbound
   2) Leibniz’s law. a. Socrates is snubnosed in actual world but not in world W.
   b. Socrates-in-acutal is snubnosed and Socrates-in-W is not.

2. Lewis’s Counterpart Theory
   Every property is a essential property

3. Inadequacy in counterpart theory(Plantinga)
   How is A somuch as relevant to B? How is A sufficient for the truth of B?

4. World-indexed property:“Being subnosed in actual world” is a world-indexed property.

6, Identifying the same object from world to world

1. Question: World-indexed property.