Posted on 11/04/2002 7:52:21 AM PST by thinktwice
Descartes was a geometrician. He found only in mathematics and geometry the certainty that he required. Therefore, he used the methods of geometry to think about the world. Now, in geometry, one begins with a search for axioms, simple undeniable truths – for example, the axiom that a straight line is the shortest distance between two points. On the foundations of such “self-evident” propositions, whole geometrical systems can be built.
Following his geometrical model, Descartes proceeds to doubt everything – de onmibus dubitandum. He will suspend belief in the knowledge he learned from childhood, all those things “which I allowed myself in youth to be persuaded without having inquired into their truth.” Doubt will be his method, a deliberate strategy for proceeding toward certainty. (Descartes is a doubter not by nature, but by necessity. What he really wants is secure understanding so he can stop doubting.)
Descartes finds that he has no trouble doubting the existence of real objects/events – our senses too easily deceive us. And we can doubt the existence of a supernatural realm of reality – figments and fantasies are too often conjured by our native imaginations. But now his geometrical model pays off: in trying to doubt everything, he discovers something that he can’t doubt. What he can’t doubt is that he is doubting. Obviously, I exist if I doubt that I exist. My doubt that I exist proves that I exist, for I have to exist to be able to doubt. Therefore I can’t doubt that I exist. Hence, there is at least one fact in the universe that is beyond doubt. “I am, I exist is necessarily true each time that I pronounce it, or that I mentally conceive it.
Descartes thus becomes the author of the most famous phrase in Western philosophy: Cognito ergo sum, or, in his original French, Je pense, donc je suis. – I think, therefore I exist. With roots in St. Augustine, this is certainly one of the catchiest ideas yet created by the human mind.
If her mind was strictly material, how could she know with certainty whether or not it was malfunctioning?
You have assumed:
--Ideas are in heads,
--There are external realities,
--Ideas (at least some) are about external realities,
--Minds are strictly material,
--Minds can function properly (else they could not malfunction),
--Minds can malfunction
All these assumptions are correct with one exception: Minds are not strictly material, in fact, the mind, which is what we call human rational/voliition consciousness, is not material at all. Material existense is that which consciousness is conscious of. One is not conscious of consciousness anymore than one can see their seeing. We know we can see because we do it, and we know we are conscious because we are.
Since you assume minds can function properly, there is no reason why Ayn Rand could not make the same assumption, and also be able to tell when it was and was not so functioning.
As for being certain "ideas in her head corresponded with an external reality...." there is no need to restrict reality to the external, because it includes the internal as well. Since both the internal and external is only that which we are conscious of, and since consciousness deals with nothing else, it is not possible that our ideas not correspond to the reality that we are conscious of, since they can be about nothing else. It's all we can have ideas about.
This assumes you do not want to take back any of your assumptions.
Hank
What's a dream?
Hank
Every statment has meaning only if the words it is comprised of have meaning. You cannot make the above statement if you do not already know what the words, certain, nature, existense, and reality mean. If you do not know what they mean, the above says nothing. At is stands, it is a self-contradiction.
Hank
There is a problem, however. Logically (metaphysically) existense precedes both consciousness and the unique human consciousness capable of thought. Epistemologically, the concept of existense, that which we are conscious of, precedes concepts that could question it. If the concept of existense itself is questioned, there is no epistemological basis for doubt, which is a negation of assertion. If nothing is asserted, there is nothing to doubt. If nothing exists, there is nothing to question. To question existense is an example of the "stolen concept" falacy. Existense, not just the concept, must be assumed to question it.
Hank
Well, you won't get any argument from me.
(But I do not believe you.)
Hank
I guess your are (as in exist) then.
Thank you!
Hank
Therefore: "I am, therefore I think".
............which is the opposite of Descartes' famous philosophical aphorism: "I think, therefore I am".
The problem isn't in her assumptions. The problem is that she (materialists) can provide no coherent explanation for truth or "the adequation of thought and reality."
In Aristotle's realist philosophy, a true thought is determined necessarily by the adequation of mind and the form of a thing. There is no gap between knower and thing known.
Your question, "how can one know that a discrete object in the brain corresponds to a discrete external object?" assumes something I do not believe is true. I believe there are events in the brain that roughly correspond to percepts of both internal and external, "objects," but the perceptions are hardly, "discrete." It is not events in the brain that I believe correspond to "external" objects, but percepts and concepts.
All of the old philosophers were never careful to identify and distinguish the difference between percepts (direct consciousness) and concepts (the identification of entities, events, and ideas, which, if done correctly, will be non-contradictory).
Since all concepts are about percepts (what we are directly conscious of) and what we are directly conscious of is what we mean by existence, both external and internal, it is not possible that concepts (ideas in our head) could not directly correspond to that existence.
There is, if you examine it, a mistaken notion in the Platonic mysticism Aristotle, and all those philosophers who follow him, have never extricated themselves from, that assumes we can know about "external" objects without first perceiving them. In fact, all that we know about we first had to be conscious of, that is, we had to perceive. All our knowledge is about and derived from those perceptions, and one of the first things we come to know is the difference between those perceptions of things external versus the internal (like our own feelings).
This distinction is not directly perceived, however. It is a concept about perception itself. Knowledge exists only at the conceptual level of consciousness. At the perceptual level we know nothing, we are simply conscious of things. All our knowledge is about that of which we are perceptually conscious. To suppose any other kind of knowledge requires some kind of mysticism.
Hank
At least Aquinas was aware of this, defining the "first act act of the mind is to apprehend reality in its intelligibility which is twofold: 1) the fact of its existence and 2) the fact of its essence or nature."
This primary object of the mind, twofold in its being, is not God, nor self, but the being that exists in the world outside the mind. We can only know this real being through our senses, but what is grasped as intelligible in the sense-object is grasped immediately in and from the sense- object by the intellect, first as it recognizes an existing thing as existing , i.e., as real, and secondly, as it recognizes the existing thing as some kind of being.
You might find this interesting.
First let me say it is nice when someone disagrees without being disagreeable. I appreciate that.
The quote above is an example of what I said earlier, "all of the old philosophers were never careful to identify and distinguish the difference between percepts (direct consciousness) and concepts (the identification of entities, events, and ideas...." I think Aquinas did have "perception" in mind when he used the term "apprehension." Other philosophers sometimes refer to perception as simple or immediate apprehension.
My point was that "1) the fact of its existence and 2) the fact of its essence or nature," are the very things perception does not provide. The "interpretation" of perception, that is, the assigning of an identity to what is perceived is at the conceptual level.
For example, I perceive a red circular patch. That perception provides nothing in itself except the fact of the percept. It is at the conceptual level that one can say, "I just rubbed my eyes, and the pressure produced the "red" spot," or "I've been looking at that green circle and the red spot is just the reaction of looking away now at the white wall," or, "I see an apple."
So even the "existence" of what is perceived is not directly perceived, nor can it be until what is perceived is identified. Again, I say, at the perceptual level, we know nothing.
Hank
This is the problem, as i see it anyway, of so many of the discussions here, not willing to understand how one arrived at the concept in the first place and then acting like it is some reified something out there waiting to be discovered. Assmptions Rule!
Thanks for the ping thinktwice, it was well worth it.
"Truth is the recognition of reality; reason, man's only means of knowledge, is his only standard of truth." -- Ayn Rand
Truth is the product of recognition(i.e., indentification)of the facts of reality. Man identifies and integrates the facts of reality by means of concepts. He retains concepts in his mind by means of definitions. He organizes concepts into propositions -- and the truth or falsehood of his propositions rests, not only on their relation to the facts he asserts, but also on the truth of falsehood of his designations of essential characteristics." -- Ayn Rand
"The truth or falsehood of all of man's conclusions, inferences, thought and knowledge rests on the truth or falsehood of his definitions." -- Ayn Rand
Regarding Ayn Rand, you wrote ... The problem is that she (materialists) can provide no coherent explanation for truth
With regard to religious "truth," Ayn Rand has a great deal to say about mysticism. Here is a short beginning, an excerpt from her essay "Faith and Force: The Destroyers of the Modern World."
Mysticism What is mysticism? Mysticism is the acceptance of allegations without evidence or proof, either apart from or against the evidence of one's senses and one's reason. Mysticism is the claim to some non-sensory, non-rational, non-definable, non-identifiable means of knowledge, such as "instinct," intuition," "revelation," or any form of "just knowing."
Reason is the perception of reality, and rests on a single axiom: the Law of Identity.
Mysticism is the claim to the perception of some other reality -- other than the one in which we live -- whose definition is only that it is not natural, it is supernatural, and is to be perceived by some form of unnatural or supernatural means.
As what?
Again, I say, at the perceptual level, we know nothing.
Then how do we know anything? Are you a nominalist? I honestly don't understand your point.
Aquinas would identify the apprehension of existence and essence (which includes composition [the substantial unity of this particular thing] and division [this thing is not that thing]) as the "first act of the mind."
How would she know with certainty whether the thoughts (chemical secretions?) in her head correspond to external realities?
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.