Here's my take on it.
Agnosticism is illogical and refutes itself. Agnosticism and agnostics characterize God as unknowable, ineffable, incomprehensible to all attempts to understand him. This doctrine is self-refuting. The agnostic is making a knowledge claim about what he/she claims is unknowable. How do agnostics know that God is unknowable if he is unknowable ? How do they even know that God's existence cannot be disproved if God is unknowable, or that God even exists if he is unknowable ? To claim any attribute for God is knowledge and claims to know this unknowable God possesses certain attributes. That's a logical contradiction, and any being containing two incompatible attributes cannot possibly exist. So one need not resort to agnosticism. He/she would be justified in not believing in that God if the concept of it contradicts itself in any way. One is justified in accepting and adopting the atheist position.
Can you be more explicit—give a page reference or at least a chapter. The book is long and sprawls over a lot of territory and Penrose tosses out an enormous number of ideas.
Apparently this dialog is actually in Penrose's Shadows of the Mind, pgs 179-190. A book I don't have either.
I have read several of his books, but not that one and I don't own a copy.
The dialog between the robot and its creator is in section 3.23 of Shadows of the Mind. It's a challenging and thought-provoking summary of Penrose's arguments from Goedel's theorem.
Shadows of the Mind was a followup of The Emperor's New Mind where Penrose tried to make his arguments more rigorous and technical. There's even a pdf online with Penrose's answer to the criticisms of his argument in Shadows of the Mind.
The programs, experience, memory, etc. can be incorporated into the basic Turing-machine model. Those things in themselves don't make us fundamentally different from a Turing machine.
but the question still remains, if a person is a Turing machine, what gets in the way of them proving their own Goedel sentence? A Turing machine has an equivalent to its Goedel sentence, as I vaguely remember (?)
Here's a paper online that summarizes the Lucas-Penrose argument that people aren't Turing machines.
One can turn it into an argument that some things are unknowable: if we are Turing machines there are truths we will never know.
but in your hard drive analogy...isn't it just a matter of learning how to do the readout? And surely there will be general principles (i.e. the software) of, for example, how memories are formed and stored, how executive function(s) operate etc
The point is that individual brains may be organized in quite different ways—that is, programmed in different languages—and without a key given in advance the task of decrypting stored messages is extraordinarily difficult and as a practical matter, impossible. It's like the problem of translating an unknown language. After all these years linear A remains undeciphered. The problem with individual brains may be much harder.
I don't believe in agnosticism as a separate classification. To me it's a qualifier of belief. That is, when I say I'm an 'agnostic atheist', I mean that I lack a personal belief in a god but I recognise that we probably won't ever know for sure (because we can't prove a negative that way). People that use the term agnostic as a stand-alone identification I tend to be suspicious of, because their opinion on whether or not the existence of a god can be factually known doesn't speak at all to their personal belief or lack thereof.
I do also classify myself as an “agnostic atheist”, but I think agnostic is a qualifier of knowledge. I am an agnostic because my lack of knowledge about god’s existence/inexistence. I am an atheist because my lack of believe in god’s existence. And I do not consider myself a “weak” atheist. I am a strong atheist, almost an antitheist.
In my opinion, based on the reading, research, and understanding (perhaps my position is wrong after all) of everything I've studied about the different branches of physics and cosmology is that science has sufficiently advanced to safely (with the condition that the science could be empirically disproved by further observation and testing) rule out the existence of any god or God. From what I know to understand I feel fine strongly having no god beliefs to the point of personal satisfaction and certainty for myself.
The word God must have a definite meaning before we can assert the possibilty of the existence of (a) God. If one does not define exactly what they mean by their idea of God then it just remains a blank. If they assert God has any qualities or capacities that are self-contradictory, that conception of God is ruled out by the law of non-contradiction. Everything about a God must be scientifically compatible with all other existing human knowledge, understandable by human reason, and possess no logically contradictory attributes or personality characteristics. Some physicists and cosmologists go so far as to say that if a God of any kind exists it should be empirically detectable. My position is that agnosticism is untenable in light of these things, not impossible, just untenable, in my opinion.
I've read and researched Dawkins, Stenger, Harris, Hitchens, Krauss, and others, and it is my strong position that there is no God. Like I said, new evidence may come to light that proves beyond a reasonable doubt that some kind of being exists outside of spacetime. Physicists and cosmologists who are atheists would not stubbornly hold onto their nonbelief if a God can be scientifically and empirically proven to exist and be the necessary cause of the universe. Strong theists, however, will not relinquish their faith for any reason or any amount of empirical evidence or logical argument. I posted a link in the past to an article from Psychology Today that said that a negative can, indeed be proven, and that the idea that a negative cannot be proven is based in folk logic, and not the kind of logic that expert professional logicians use. Here is a link to another site explaining how you can prove a negative.
my belief,(not faith, which is "trust in things not seen or proven and without evidence) is in things that are evident and have proofs and are repeatable and, if new evidence comes along I am allowed to change my view based on the new verifiable evidence. Some others believe in "faith" that offers no such thing. It demands an adherence to dogma regardless of the evidence and proofs. I will stay with reality, not the dangerous role play game that others have chosen to engage in. Agnostics seem to think, according to your description that the "metaphysical" might actually be a reality. sorry, I dont think so myself. I am a pure "anti-metaphysics" kind of person. So as I see it, agnosticism is just a fancy "pascals wager" and equally , realistically and philosophically useless.
you either live in reality or you believe, even passively in metaphysics.
you either live in reality, or you dont.
to believe in metaphysics, you might as well be living in a fuckn monastery, or washington D.C.
booth equally out of touch with reality.
One of the core beliefs of religion is that the physical world isn't all that there is.
I don't see how anyone can be positive that this is false.
It might be actually wrong, in the sense of parallel universes, etc. Even dark matter is a kind of reality that' outside our usual physical world in the sense that it interacts only gravitationally. It becomes a matter of definition - what is meant by the "physical world" vs. metaphysical.
Even the idea of some kind of overarching consciousness that has power over the world, is a possibility. If you are positive this is wrong, like any other idea I would say prove it!
Since there is already a good psychological explanation that someone would think such a thing, that is my explanation for the human God-perception, and it would take a lot to persuade me otherwise.