(October 5, 2013 at 11:52 pm)Rational AKD Wrote: this is another complex argument developed by Plantinga. it uses modal logic so it may be difficult for some of you to grasp. since it seems many people misunderstand the purpose of my prior arguments, i'm going to be more clairvoyant with my arguments by establishing the purpose before I share the argument.
Purpose: many atheists claim the afterlife is impossible since the mind and the brain are the same. my aim is specifically against those claims, showing they are in fact not the same and establishing the independent function of the mind from the brain is possible.
Argument:
P1: it is possible (meaning conceivably possible) for the mind to act independently of the brain.
P2: it is impossible for the brain to act independently of the brain.
C1: there is an aspect of the mind that is different from the brain (P1, P2).
P3: if two things are the same (meaning same identity), they must have exactly the same aspects and properties. if there is a single aspect that is different, then the two are not the same.
C2: the mind and the brain are not the same (C1, P3).
Conclusion: the mind and the brain are not the same thing, therefore it is possible for the mind to function independent of the brain.
Objections:
1. this doesn't prove the mind can function independent of the brain-- correct. it only proves it's possible, which is all this argument aspires to establish.
2. but what happens to the brain can affect what happens to the mind, so that proves they are the same-- that may be true, but that only establishes a connection not an equivalence. the brain can affect the mind without being the same as the mind.
3. P1 is false therefore both conclusions are also false-- in that premise I was speaking of conceivable possibility. it would be easier to understand that with some basic knowledge of modal logic. what it means though, is we can conceive of such a thing happening without creating a logical incoherence. it can be shown that it is not incoherent by the numerous stories/movies of people who have their minds switched, or transferred, or astral project. we can conceive of such things without thinking it incoherent, therefore it is conceivably possible.
The fallacy is strong in this one.
1. Strawman Fallacy - Atheists argue mind-brain equivalence, not mind-brain identicality. If you show an atheist the brain of a dead person, he would typically not argue that it is a mind as well. He would not regard chunks of neurons as mental events. When someone says "mind is brain", it is a trite way of saying "a functioning brain gives rise to the phenomenon identified as mind". This distinction should be obvious after reading the explanation of any monist philosophy. Thus, the claim you are trying to disprove has never been made in the first place.
2. Fallacy of Equivocation - In your "objections" 1 and 3, you equivocate between "possible" and "conceivably possible". That something is conceivable does not prove it is possible (Its relation to logical incoherency is explained in the next argument). "Conceivably possible" means that it is possible to conceive of such a thing and that conceivability depends upon an individual's power of imagination and the factual premises he chooses to ignore. That does not make what he conceives actually possible
3. Argument from Ignorance - Or rather, argument from willful ignorance. By ignoring an aspect of an entity's essential nature - typically, an aspect not within direct perception - what would otherwise be logically incoherent becomes "conceivably possible". The trick is simple - ignore an essential aspect of an entity's identity, substitute is with something similar so that it appears the same and the previously inconceivable becomes "conceivably possible". For example, having never heard the official definition of a bachelor, suppose I identify a bachelor as "someone with no apparent permanent companion, living alone, hanging out with similar friends, picking up girls, partying etc." - then the idea of a married bachelor becomes "conceivably possible". Similarly, for a blind man, having never seen the visual representation of a circle and only knowing it as a shape with no vertices, the idea of "square circles" or "triangular circles" is equally conceivable. Similarly, ignore that the DNA makeup of a horse is essential to defining what constitutes a horse and ignore that that DNA makeup does not support feathers - and suddenly, Pegasus is no longer logically incoherent but "conceivably possible".
You are doing the same thing here. As do the movies depicting mind-switches, transference or astral projection. Ignore the essential functional nature of the mind which requires the physical functioning system called brain - regard it, instead, as a disembodied spirit - and suddenly, mind acting independently of the brain becomes "conceivably possible". However, the fact remains that conceiving of something by ignoring its factual nature does not change the factual nature - thus separating what is conceivable from what is possible.
4. Circular Reasoning - Which is, basically, what this whole argument is in an elaborate form. For the very first premise to be true, i.e. in order to conceive of mind acting independently from brain, you have to assume that mind and brain are two separate and distinct entities. Without that assumption, the very first premise would be logically incoherent. Thus, you are implicitly assuming from the start that mind and brain are distinct entities and concluding, based on that assumption, that mind and brain are not the same thing.
Poor showing. A very poor showing.
