Valid: an argument is valid if and only if it is necessary that if all of the premises are true, then the conclusion is true; if all the premises are true, then the conclusion must be true; it is impossible that all the premises are true and the conclusion is false.
Invalid: an argument that is not valid. We can test for invalidity by assuming that all the premises are true and seeing whether it is still possible for the conclusion to be false. If this is possible, the argument is invalid.
Validity and invalidity apply only to arguments, not statements. For our purposes, it is just nonsense to call a statement valid or invalid. True and false apply only to statements, not arguments.
No. That is not what I said.↪Banno So you really think all arguments that take p implies q as a premise are invalid? — flannel jesus
Do you think it's possible for you to think if you don't exist? — flannel jesus
I've answered that — Banno
I do not think the Cogito convincing, on Tuesdays and Thursdays. Monday, and Wednesday, I'm quite convinced. Friday and Saturday, I take an agnostic position. Sundays, I rest.Do you think it's possible to think without existing? — flannel jesus
That's not really what you said though, is it?. Anyway, I'll take the belated honest answer given here, you don't know. Wonderful.That was an honest answer: I don't know. — Banno
It indicates a process of thought not a proces of causation or chronology. The detective's thought process, not the scientists proclamation of causation and order in time.
So, again, I think you misunderstand 'therefore' and are confusing word order with a diagram of events in time. — Bylaw
So, do we agree that "p⊃q" is invalid? — Banno
Valid: an argument is valid if and only if it is necessary that if all of the premises are true, then the conclusion is true; if all the premises are true, then the conclusion must be true; it is impossible that all the premises are true and the conclusion is false.
If yes, then do we agree that the Cogito is "I think, therefore I am"? — Banno
If no, then what is the Cogito? — Banno
1. I think ⊃ I exist. (Cogito, assumption)
2. I think. (assumption)
3. ⊢ I exist. (1.2, MPP) — Banno
That as such, it would be circular? — Banno
And it seems we agree that the Cogito is — Banno
Then, returning to the topic, do we have some basis for thinking that this intuition counts as part of the 100% certain knowledge that the OP seeks? — Banno
I am isn’t a conclusion. It’s as much the premise as the conclusion. It’s just a premise that self-certifies it’s fact as a premise. — Fire Ologist
Therefore it has implications of chronology and cause and effect transformation for the antecedent being the past, or cause, and the descendant to imply the result, consequence and effect.
If you deny that standard meaning, then you are denying the general principle of linguistic semantics. And that is what you have done to mislead the argument and further present the nonsense. — Corvus
I swim, therefore I am wet.
If you define swimming as propulsion through water, then being wet is contained in, or comes along with, or is a consequence of, swimming. — Fire Ologist
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