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Luke

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Why not? Why?
July 10, 2022 at 07:31
No, that's not that same as what you said here: If the present moment is "when our sensations tell us it is", then p is present when our sensations te...
July 10, 2022 at 06:27
That's what I'm saying, too. I assume we have been using t1 and t2 as follows: t1 = the time that an event occurs t2 = the time that we become aware o...
July 10, 2022 at 06:01
Only if you define presentness, or the present, in that way. I am not denying that an event occurs at t1 and that we are aware of it at a later time t...
July 10, 2022 at 05:48
To determine that your sensation falsely represents the event p as being in the present (at t2) presupposes that t1 is the present, not t2. My point i...
July 10, 2022 at 04:59
Have you heard that seeing stars (or starlight) is looking back in time? So when you look at the stars you might be seeing light that was reflected fr...
July 10, 2022 at 04:13
Yes.
July 10, 2022 at 03:53
I don't consider it to be an issue of materialism vs idealism, but an issue of how to define the present moment. Is the present moment defined as the ...
July 10, 2022 at 03:40
That is, the world is the totality of states of affairs, not of things. A state of affairs is a combination of things. "States of affairs" and "things...
July 10, 2022 at 03:02
I don't see how the conclusion follows. It seems to follow only that nothing eats goats. EDIT: ah I see now.
July 09, 2022 at 05:13
Perhaps I'm just confused by: "K is...used in the future-tense in standing for "Eventually it will be known that ...". Do you mean anything different ...
July 09, 2022 at 02:53
I'm not saying you're wrong; I'm merely noting that what you have said appears to contradict what @"sime" has said. Does the Fitch proof use a non-sta...
July 08, 2022 at 06:06
I’ll try and come back to the rest of your post, but if the above is correct, then this would seem to contradict @"Michael"’s claim that a proposition...
July 07, 2022 at 13:56
Oh cool, thanks.
July 07, 2022 at 08:39
I was hoping someone would have responded to this point. Did anyone else note this connection between the two paradoxes? Does anyone agree or disagree...
July 07, 2022 at 07:48
I can see now that I was wrong about this, and I now accept that some truths are unknowable. Thanks to you and to @"Andrew M" for your patience and fo...
July 07, 2022 at 06:03
Is (2) both true and false? Is (3)?
July 06, 2022 at 14:06
I didn't realise that they were premises; I thought they were unrelated statements. If knowing 2 makes 1 unknown, then how is 1 knowable? That is, if ...
July 06, 2022 at 12:41
What does "p ? ¬Kp" represent if not that the cat is on the mat AND that it is not known that the cat is on the mat? "p" does not represent that p is ...
July 06, 2022 at 12:25
If p is an unknown truth, then it is represented by "p ? ¬Kp". It's that simple.
July 06, 2022 at 12:12
Likewise. Every truth ("p") is either known ("p & Kp") or unknown ("p & ~Kp"). There are no other known or unknown truths. Your mistake (and mine, too...
July 06, 2022 at 12:08
It is unknowable that p is true and that somebody knows p is true? Why is it unknowable? You claim that "p" can be unknown and knowable. But if all tr...
July 06, 2022 at 11:08
Our dispute is over your claim that there are knowable unknown truths. If all truths can be expressed as either: 1. p ? Kp ; or 2. p ? ¬Kp Then which ...
July 06, 2022 at 10:26
Then you misunderstood that I was expressing both known and unknown truths. This removes the ambiguity of your unknown truth expressed merely as "p". ...
July 06, 2022 at 08:55
Okay, but I removed the ambiguity by expressing known and unknown as: To which you said "we write it as": That's either making it ambiguous again (if ...
July 06, 2022 at 08:52
I thought you said "p" could either be known or unknown?
July 06, 2022 at 08:48
Don't leave it ambiguous then. If truths are either known or unknown, then this can be expressed as: 1. p ? Kp; or 2. p ? ¬Kp 1. is knowable. 2 is unk...
July 06, 2022 at 08:42
Isn't that unknowable?
July 06, 2022 at 08:19
Yes, that's the reason that we can't know both a) and b). Again, I'm not disputing the logic, only its implications. We cannot know both a) and b) mea...
July 06, 2022 at 08:15
3 only says that p is true, not that it is true and unknown.
July 06, 2022 at 08:07
We did, but I didn't realise then, and wasn't making the point then, that the issue was with logic and not with knowability. You claim that we can kno...
July 06, 2022 at 07:59
You're right. I meant to say that it is never known to be true. According to logic, if it is true and unknown that there is milk in the fridge, then i...
July 06, 2022 at 07:22
I accept that, according to the logic, "p & ~Kp" is unknowable. However, I don't think this is an issue for knowability, but an issue for logic. "p & ...
July 06, 2022 at 07:19
I accept that. But it is only wrong in the sense that one cannot both know the proposition and know that it is unknown. Knowing it negates its being u...
July 05, 2022 at 13:19
From the little I've read, they seem to be looking to qualify the theory in some way (as Andrew put it). For example: I accept that the problematic st...
July 05, 2022 at 13:12
Surely it is never true. If a statement is known to be true, then it cannot also be unknown to be true ("by somebody at some time"). Which is what the...
July 05, 2022 at 12:56
Just don’t set it too low, in case we need one more.
July 04, 2022 at 05:21
It just seems counterintuitive to me that any unknown truths should be unknowable in priniciple. If the only unknowable truths are that 'p is true and...
July 02, 2022 at 23:15
I get it now. Unknown truths can either mention they are unknown or not mention they are unknown. Only the former are unknowable. Since there is at le...
July 02, 2022 at 14:52
You want to disregard Fitch's proof, but I'm the one changing the subject? Either an unknown truth is expressed as “p & ~Kp” and it follows that we mu...
July 02, 2022 at 13:55
Then we can simply express the unknown truth in Fitch’s proof as “p” and the problem goes away: there are no unknowable truths. EDIT: Does Fitch’s pro...
July 02, 2022 at 11:46
How does that express that it is unknown?
July 02, 2022 at 11:27
So is there a way to express an unknown truth in logical notation without mentioning that it is unknown?
July 02, 2022 at 11:13
Are you saying that we can change the expression of the unknown truth in Fitch’s proof to “p” instead of “p & ~Kp”?
July 02, 2022 at 10:52
Please tell me where I am going wrong here: The unknown truth that is the number of coins in the jar is expressed as: p ? ¬Kp It is impossible to know...
July 02, 2022 at 09:47
I'm asking you how else "p is unknown" could be expressed in logical notation - other than as "p ? ¬Kp", and other than as your mere assurance outside...
July 02, 2022 at 09:22
2 (when expressed as "p & ~Kp") is unknowable, which means that so is the number of coins in the jar. It is not possible to know any proposition of th...
July 02, 2022 at 09:04
Then this should be able to be expressed in the argument. If it cannot be expressed in the argument, then it is not a failure of the knowability princ...
July 02, 2022 at 08:54
1. does not express that it is unknown 2. expresses that it is unknown, but it is unknowable. Therefore, the number of coins in the jar remains unknow...
July 02, 2022 at 08:49
Presumably, the unknown truth of the number of coins in a jar is not expressed as "p & ~Kp", since this is unknowable. So how would you express the un...
July 02, 2022 at 08:36