August 2, 2010.
Example: I know there is a table in front of me (both sides agree: if I know anything, I at least know that)
Skeptic rejects that, and therefore rejects that you know anything
Many different skeptical arguments, often of the form “There exists a scenario in which you are having the same phenomenological experience yet there is no table, so how can you know whether you are in that scenario vs the genuine experience scenario?”
Examples: dreaming, evil genius, brain in vat (Putnam)
Logical priority of conventional methods of determining thoughts over brain scanner
There is a causal dependence between brain activity and experience, but it is a leap to suggest that we can identify brain activity with experience.
Even if we found an incredible empirical correlation between brain activity and experience, if we suddenly had a conflict one day (brain scanner says that the subject thinks he’s drinking coffee, but we see him eating ice cream and he assures us he knows/believes he is eating ice cream), then we would conclude the brain scanner is wrong, not the
What it means to be a thought is not the same thing as what it means to be a brain state
Brain states connected by casual relationships. Cannot be ‘correct’ or incorrect.
Mental states occupy the space of reasons - the meaning of certain thought is identified by its relationships to other thoughts. Structured by normative relationships (can be correct or incorrect).
If brain scanner with amazing correlation says that someone is telling a lie by analyzing brain states, they may be lying 100% of the time that brain scanner says they’re lying, but it is not the brain state itself that makes them lying or not.
Drawing from thoughts of John MacDowell (“Mind and World”)
For a thought to be ‘about’ an object (world-directed, with empirical content) - it’s necessary that the correctness of the thought to be answerable to how things are.
For an intention to be an intention - it has to determine the correctness/incorrectness of some subsequent action.
A brain is not logically answerable to reality and is not overtly acting in the world, so it’s not fair to say it has thoughts or intentions.
This is not a general anti-skeptic argument, but other skeptical tactics might be addressable by similar reasoning.
Thus, Edward is proposing bottom up anti-skepticism, rather than some top-down “reason for knowing that the table is there”
Stanley Cavell has written well about how skeptical lines of thought arise naturally (i.e. they are not purely the product of academic philosophy).
Skepticism shows up in lots of fields/subfields of philosophy, and it’s important to prevent the confusion that arises here from spreading. (e.g. brain scanner is relevant in legal topics)
(written in 2018) - 1A: Logical priority of conventional methods of determining thoughts over brain scanner - Is this related to the fact that the brain scanner is purely correlation, rather than based on some fundamental theory? - If we had a more fundamental theory that the brain scanner’s workings fit in with (e.g. quantum mechanics), then we would be more likely to embrace the absurd scenario of the subject being insane (and/or we failed to identify his environment) rather than saying quantum mechanics is wrong. - Surely there are historical examples where X is a ground for some technique Y, but for various reasons eventually Y becomes ground for X? - Logically-prior = closer to the ‘center’ of the web-of-beliefs. - Furthermore, this example only works if it is possible that there is a conflict (in the world where there is perfect correlation, then we can identify brain activity with thoughts) - 1B: “To be a brain state is one kind of thing, to have a thought is a different kind of thing” - This is a good point towards saying they are not ‘literally’ identical, in the sense of “My dad’s wife” and “My mom” being literally ‘different’ (they have different truth conditions) but may be equivalent given some state of affairs. - This is perhaps sufficient to say “no reason to think brains in vats can think” … but at least it’s sufficient for “there is a reason to think brains in vats cannot think”. - What this argument does not show (which maybe Ed is advocating) is that it is incoherent to identify brain states with mental states. If we can identify them, then they both are both kinds of things and there are no - There may be an isomorphism between the “logical space of reasons” and the space of brain states related by physical causality. - If brain states (and their relations) were in bijective corrspondance to thoughts, then we can refer to a brain state by its thought and vice versa. Whether or not this is the case is precisely the debate at hand, but bringing this point up does not advance the argument one way or another. - How to decide whether to believe such an isomorphism likely exists is complicated. - 2: - The belief that there is a table in front of me (even in brain-in-vat scenario) IS answerable to reality (and the the belief is false). Likewise for intentions (the intention will be unfulfilled, unless one is desiring to be a brain in a vat) - How does this bear on the legality of killing comatose people (they are in an analogous situation)