I thunk that you can't really know anything beyond "reasonable" doubt. I could say "I know the marble is white", and by that, I would mean: "I am mostly sure that my senses told me the marble is white". So that solves the brain in a jar problem, since even if your brain is in a jar, what your senses tell you, doesn't change, what changes is only where the input comes from, and that input might or might not come from "reality", but that doesn't matter in this context, since you are just stating what your senses perceived, not what reality is (and to you, this is reality anyway, since there is no practical difference). So, I do think that we can't actually claim to "know" anything without any doubt, but we can state what our senses perceive, and what we think we remember our senses perceived in the past.
I'd think the closure principle is not entirely justified. Let's take a look at a classical example: obviously, "Lois Lane knows that Clark Kent is Clark Kent". Since Clark Kent *is* in fact Superman, then 'IF Clark Kent is Clark Kent, THEN Clark Kent is Superman'. But Lois Lane does *not* know that Clark Kent is Superman. The Closure principle is (IMO) more correctly formulated as: "If the agent knows P, and the agent *knows that* P implies Q, then the agent knows Q". But that second stipulation, that the agent must know about the implication, cannot simply be dropped. Note that, at least for academics, this does not solve the 'brain in the vat problem', because people versed in philosophy know about the implication "if what I'm experiencing is real, then I'm not a brain in a vat". Lastly, I would like to note "one man's modus tollens is another's modus ponens'; what this means here, is that we can (similarly to Moore's 'here is one hand'-argument) say that "Since I know the marble is white, I know that I'm not a brain in a vat". While this may seem strange, there's actually some really interesting literature on why this kind of argument does or does not work (for instance Wittgenstein's 'On Certainty').
+Your2ndPlanB Great addendums! "On Certainty" was one of my inspirations for this episode, & I think you give some good detail on closure. (The "run closure backwards" thing is actually what the construction crew in the opening segment is debating. ;) )
One could even make the point that someone doesn't even 'know' the conclusions of an argument until they've actually made it. We've probably all been in the situation where someone says "obviously X is true", where we did not see why this was the case (at least as a mathematican I have been there many times). However, once they explained why X was true, we could agree that the argument was correct, and we ourselves knew everything they used. The closure principle would dictate that we knew X all along, we just didn't *know* we knew it! Depending on which way you want to bite the bullet, either we didn't know X (which poses a problem for the closure principle), or we can know things without knowing it.
Couldn't one argue that knowledge is simply never absolute? For knowledge to be absolute one would have to have every variable, which may not even be possible. I think we all have knowledge, just incomplete knowledge.
I’ve said it before and I’ll say it again: your channel is (by FAR) the most underrated channel on this entire website. Please keep up the good work and remember that there are viewers (me included!) that get excited when they hear that you’ve dropped a new video :)
I think that being capable of deducing the knowledge isn't the same as actually deducing the knowledge. I can't tell you how many times I've gone on doing something only for it to be ruined by me not doing another thing that's required, despite "knowing" full well it's necessary. I just never gave it any mind. Or puzzles where the thought never even occurred to me that such a thing could be the solution, despite it making full sense and following from knowledge I held in my mind at the time.
I'd posit that "knowledge" as we intuitively understand it is more accurately described as heightened confidence. If I know you pulled a marble from a jar, and the only jar I'm aware of is full of white marbles, then, I "know" you pulled a white marble whether or not you actually did, because I can be as confident about that being the case as I can about anything I've observed directly. Essentially, if our knowledge checklist is reduced to require merely justification and belief, then the definition seems to match up with our intuition. As for actual, unshakable truth, we should probably find a new word for that with fewer connotations :P
Would you be comfortable asserting that children *know* that Santa Claus exists? After all, they have confidence heightened by direct observations & evidence.
In the morning I get on a flight from Bombay to Moscow.I know that night I will be in Moscow..... I spend the next three days in Pakistan because a general terrorist alert in the region grounds all flights..... Really happened to me, the Closure argument, empirically tested and failed.
I'd say there are only 2 things you can know with absolute certainity: Things that are based purely on logic (like if A implies B and B implies C, then A implies C) The fact that there's currently something that identifies as "you" and has a subjective experience. However, there are several things where you can be pretty damn sure that they're true, so you can "know" things if you count "I'm 99,999...% sure of X, and that degree of certainity is justified" as knowledge of X.
THUNK Again not sure what to think or thunk of this video. Many of your videos I will go over and over again till I get some understanding of what they mean. I am not much interested with western philosophy, except when it comes to Ludwig Wittgenstein. Philosophy to me is long winded. It most likely has to do with my inability to grasp it. I will put this video in line with the other videos I will watch again.
If you're a brain in the jar, the knowledge that you have about the context in which you live is still knowledge? isn't it? Even if I live in the Matrix (and I'm obviously not the ONE), if I jump I always come back to earth... So I can have knowledge about the world, even if it might be a simulation. Internally it is consistent.
If you *really* throttle down on what "knowledge" is like this ("internally consistent observations, regardless of their actual truth value") you get into weird places, like children "knowing" that there is a Santa Claus - after all (so long as the illusion is preserved) they have made internally consistent observations of his passage!
THUNK True, but shouldn't I only be questioning that belief if I see a contradiction? And if I see that contradiction shouldn't I also consider the possibility of the observation being false while considering the possibility of that original interpretation not being accurate and only gradually becoming more skeptical of it as I identify more contradictions over time?
The difference between "belief" & "knowledge" is kind of what's at stake here. There are all sorts of useful heuristics for "beliefs," like the one you've mentioned, but are you willing to relegate all "knowledge" to mere "a belief that I haven't seen contradictory evidence for yet?" Does it make sense to question your belief that 1+1=2, & is that of the same class as belief in Santa Claus for someone who hasn't seen evidence that he doesn't exist?
It's only a problem because we don't want it to be true. OBut even if we are just a brain in a vat, we (well actually just: I) can still be pragmatic about it.
I don't know what the answer is, but this just shows that it's best to just use induction for everything. Just use a base case that doesn't involve a brain in a vat.
I mean I did that one episode on the Motte & Bailey fallacy & "The Vacuity of Postmodernist Methodology," that should restore my postmodern karma somewhat. ;)
I know this is a good video, I know good videos lead to very popular channels...this channel doesn't have nearly enough subscribers for how good the videos are... therefore was it really a good video????
I mean, maybe it's useful to think about knowledge and its relationship to certainty differently? I feel like, when I think I know something about the world, your brain gives you this "feeling" of certainty. But maybe certainty is just that, a feeling that brain makes for us, so that it's easier for us to proceed with life and make decisions. Underneath I think our brains are just probability calculators. This is how I tend to actually see things anyways. Think of it as a gradient between the purple unicorn guy and my knowledge that "the sun will rise tomorrow". Both of us "just got lucky" to some degree, mine is to a much lower degree but both are really just probabilities. Maybe even think of my knowledge behaving asymptotically to certainty or truth. It gets super close, but never touches. Otherwise if we say you have to have actual certainty in order to have knowledge; well then I think you're just chasing an abstract ideal that doesn't exist in the universe. Personally I'm pretty partial to just throwing out the idea of certain truth anyways. Chasing these ideals in various forms, seems to be so pervasive in our culture. God damn Plato.
This was actually what I was talking about last episode with Bayesian epistemology - with rigorous rules for inductive inference, you can approach certainty asymptotically (just as you're suggesting)!
