Questions pertaining to logical constructs

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1
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2answers
522 views

Improper usage of “subsequently” in the latest Futurama episode?

In the latest Futurama episode, called Cold Warriors, the professor says the following: The common cold died out 500 years ago and subsequently humanity lost all resistance to its ravages. ...
8
votes
1answer
7k views

Difference between “subsequently” and “consequently”?

When studying and reading course material in "softer" sciences that are descriptive the word "subsequently" appears in a way like "and subsequently" ...what does it mean, disctinct from "consequently" ...
5
votes
2answers
708 views

“There is no doubt this is arguably wrong”

This is from a review of something: There is no doubt that the (product name) is arguably the best consumer (product category name) currently on the market. I stopped for a while after reading ...
10
votes
5answers
23k 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
1k 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 ...
12
votes
7answers
4k views

Does 'some' necessarily imply 'not all'?

If some X's are Y's, does that imply that some X's are not Y's?
5
votes
6answers
952 views

Is there a common English phrase for the 'so absurd it must be true' logical fallacy?

There are various common (often Latin) phrases for various logic fallacies, such as post hoc ergo propter hoc, argumentum ad populum, slippery slope fallacy, etc. Is there a common phrase used to ...
3
votes
2answers
2k views

Usage of “if and only if” as a nontechnical term

The phrase "if and only if" (iff) is commonly used in the field of mathematics (⇔) and computer programming, as a conditional expression in classical (Boolean) logic. Within that scope, it might not ...
7
votes
5answers
656 views

Does this logical fallacy have a name?

A phrase being used by the "news" media regarding the recent arrest of people in Columbus, NM is "firearms favored by the Mexican cartels", referring to their purchase of AK47s and other ...
18
votes
7answers
16k views

Does “either A or B ” preclude “both A and B”?

In mathematics, "A or B" includes "A and B". Does "either" mean "A or B but not (A and B)" or does it include the possibility of "A and B"? The context might be mathematics, formal logic or ordinary ...
9
votes
5answers
93k views

“Centered on” or “centered around”

I have often heard presenters talking about something centered around another thing, but it seems a bit illogical and hence improper to talk like this. Am I right about this?
6
votes
6answers
939 views

The word 'not' often doesn't mean total negation in mathematical sense?

Consider the following conversations: X1: I paid $10 for that hamburger. Y1: That's not cheap! X2: I pay $1 for broadband Internet access. Y2: That's cheap! X3: I paid $1 for a hot ...
4
votes
2answers
360 views

Is it true that

Is the following sentence grammatically incorrect? Is it true that 1+1=2 ? I know it is easier to say: Is 1+1=2 true?