Can someone check this to see if it follows
- Burning ghost
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Re: Can someone check this to see if it follows
Break this down into notion:
P1) - p (not p)
P2) reiteration of P1 so this is redundant.
P3) B is a subset of A.
P4) -p -> -p (basically this is P1)
P5) reiteration of P4.
That’s it. Nothing more is there?
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Re: Can someone check this to see if it follows
It is about the logic of knowing and believing, based on the definition of knowledge, which can be "justified true belief" or something added to this definition. Alias said the core of what the OP tried to say: if I know p is false, I cannot believe p is true. But p4 is not right, and p5 adds no information.Burning ghost wrote: ↑June 28th, 2018, 1:48 pm If so then P4 and P5 are identical.
Break this down into notion:
P1) - p (not p)
P2) reiteration of P1 so this is redundant.
P3) B is a subset of A.
P4) -p -> -p (basically this is P1)
P5) reiteration of P4.
That’s it. Nothing more is there?
- Burning ghost
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Re: Can someone check this to see if it follows
p->q where p is the statement “I know x is false”, and q is the statement “x cannot be true.”
Note: (p->q) <=> (-p v q) which means “I know x is not false (ergo true) OR x cannot be true.”
The OP states “contradiction” but there is no contradiction just a lack of understanding of how to apply logic to sentences.
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Re: Can someone check this to see if it follows
That is right, but also "If I know x is false, I cannot know x is true" and "If I know x is false, I cannot believe x is true", which were the sentences in the OP.
(-p v q) means "Either I do not know that x is false OR x cannot be true". But this was not the sentence of the OP.Burning ghost wrote: ↑June 28th, 2018, 3:39 pm p->q where p is the statement “I know x is false”, and q is the statement “x cannot be true.”
Note: (p->q) <=> (-p v q) which means “I know x is not false (ergo true) OR x cannot be true.”
- Burning ghost
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Re: Can someone check this to see if it follows
They are equivalent that is what the <=> means.(-p v q) means "Either I do not know that x is false OR x cannot be true". But this was not the sentence of the OP.
To see this simply apply a more tangible sentence.
“IF I am alive THEN I am not dead” is equivalent to saying “I am not alive OR I am not dead.” (They are the same.)
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Re: Can someone check this to see if it follows
I know, but your description of it was not right. Compare your version with mine above.Burning ghost wrote: ↑June 28th, 2018, 10:00 pm Tam -
They are equivalent that is what the <=> means.(-p v q) means "Either I do not know that x is false OR x cannot be true". But this was not the sentence of the OP.
To see this simply apply a more tangible sentence.
“IF I am alive THEN I am not dead” is equivalent to saying “I am not alive OR I am not dead.” (They are the same.)
- Burning ghost
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Re: Can someone check this to see if it follows
I say this because if I say “I know x” it different from saying “x is x.” So to say “I know x is false” is just to state “x is false” the negation of which leaves us with “x is not false,” not “I don’t know x.”
There was a reason I brought up semnatics. Many sentences need cutting up carefully before moving ahead with the logic. I am well within my right to say what I’ve said. I am not wrong, “knowing” has very little to do with it
If I am wrong I am wrong.
Does the sentence “I know x is false” not alter at all? doesn’t it say simply “x is false.” ??
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Re: Can someone check this to see if it follows
There is a big difference.Burning ghost wrote: ↑June 29th, 2018, 6:32 am Does the sentence “I know x is false” not alter at all? doesn’t it say simply “x is false.” ??
If x is false, I need not know x is false, and I can believe x is true.
If I know x is false, x is false, and I cannot believe x is true.
This was the problem with the OP, although its conclusion was right.
- Burning ghost
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Re: Can someone check this to see if it follows
The OP made more sense than that, but I understood it was based on strange definitions of “belief” and “knowledge.”
Oh! Just got it. Again, the issue is with the “know” and “belief.”
For dumbos like me it is best to say:
P1) x is false.
P2) I know x is false.
P3) knowledge a subset of belief.
Then using P2 proceed.
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Re: Can someone check this to see if it follows
Right. But why did my previous post not make sense?Burning ghost wrote: ↑June 29th, 2018, 9:02 am That makes no sense to me whatsoever.
The OP made more sense than that, but I understood it was based on strange definitions of “belief” and “knowledge.”
Oh! Just got it. Again, the issue is with the “know” and “belief.”
For dumbos like me it is best to say:
P1) x is false.
P2) I know x is false.
P3) knowledge a subset of belief.
Then using P2 proceed.
- Burning ghost
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Re: Can someone check this to see if it follows
2023/2024 Philosophy Books of the Month
Mark Victor Hansen, Relentless: Wisdom Behind the Incomparable Chicken Soup for the Soul
by Mitzi Perdue
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Rediscovering the Wisdom of Human Nature: How Civilization Destroys Happiness
by Chet Shupe
March 2023