1
vote
3answers
185 views

How do definitions of words imbue meaning? [closed]

How do definitions of words imbue meaning? To give you a gist of what I try to discover, I'll define a collection of sets of words and show that their intersection contains all 'circular defined' ...
6
votes
3answers
224 views

Difference between “not every” and “every … is not”

I've always understood that you can order the words not and every (or similar words) in the following two ways to convey distinct logical meanings. Every human is not a man. There is no human being ...
0
votes
1answer
66 views

Can “refute” be used with “that” clauses, and if so, what is the meaning?

I refute that A is B. If this structure is ok, which of the following does it mean: I argue that A is not B. I argue against some other position (such as X is Y), by arguing that A is B.
18
votes
7answers
6k views

“All that is gold does not glitter”

"All that is gold does not glitter" is the first line of a poem from the Lord of the Rings and it's supposed to mean "not all gold glitters" but I'm struggling to see how this can be deduced. If all ...
2
votes
2answers
344 views

Unambiguous Way of Stating a Biconditional in Plain English

I am having a hard time understanding this section in Wikipedia's article on Logical biconditionals: Colloquial usage One unambiguous way of stating a biconditional in plain English is of the ...
2
votes
3answers
1k views

What does “an A/B metaphor” mean?

I wonder what "an A/B metaphor" means, for example, in the following quote from Wikipedia about formal language: "In some applications, especially in logic, the alphabet is also known as the ...
9
votes
5answers
7k views

“If” vs “Only if” vs “If and only if”

If I said: Yell only if I fall. Would the person have to yell once I fell? Sources of confusion Wikipedia This guy
4
votes
3answers
939 views

'Therefore' in an illogical logic sense

I have a co-worker that is always saying "Therefore, A B C" when the "A B C" isn't a conclusion from any sort of deductive reasoning. For example, Me: ... thus, that's how it works. Her: I ...