44

Do you have a proof that we don't hold ourselves to higher standards? There's actually a rather interesting little corner of mathematics called "proof theory." It deals with the question of what a proof is and how can we use them. It starts to look like philosophy from time to time. I think the real difference is that mathematics typically starts with a ...


33

This is not a fallacy, just the old problem of induction. A case of hasty generalisation would be to conclude that the witness tends to lie, if you have observed it two times in a row.


32

All informal fallacies take their force from their similarity to strong arguments. In this case, if you say "This boy lied 19 days in a row, therefore we have good reason to disbelieve him on Day 20," that is a perfectly good argument (assuming it isn't suppressing other relevant information). But if you say "This boy lied 19 days in a row, therefore what ...


19

I think I found something that comes close: Appeal to probability (Wikipedia) An appeal to probability (or appeal to possibility) is the logical fallacy of taking something for granted because it would probably be the case (or might possibly be the case). and An appeal to probability argues that, because something probably will happen, it is ...


18

If I'm understanding your question correctly, then you're basically asking "why doesn't philosophy have the same level of rigor as mathematical proof?" I think there's two parts involved in answering this. First, one aspect of philosophy for many philosophers (arguably all) is that philosophy is actually a form of history, meaning we are studying ideas ...


14

Philosophical theories are more like scientific theories than mathematical theories, in that they have empirical content. As such, there aren't any (universally agreed upon) "first principles" that must be respected. Any potential first principles might get discarded if the reasons for doing so are compelling enough. And even if there are some such ...


10

A proof is only as strong as the axioms it is built upon. Mathematics works over a very limited number of strong axioms to work with, which gives it a limited number* of things that can be proven, but the proofs are very strong thanks to the axioms they work with (and prior proofs relying on the same axioms). Philosophy works with much broader field of ...


9

A statement of the form "If X then Y" where Y is true, is always true in classical logic. If the consequent of a conditional is true, then it matters neither what the antecedent is, nor whether there's any actual connection between them. In this case, your "Y" expresses a mathematical truth, so we can take it as being a proposition that is always and ...


9

There is nothing right or wrong about the use of analogy as such. It is really only a statement. It says A is to B as C is to D. There is no argument, no logical inference. The analogy is valid, correct, persuasive, illuminating depending on whether (as a matter of fact, not of logic) A really is to B as C is to D. An analogy always depends on some ...


9

Because it would then cease to be philosophy. Philosophy sees itself as the progenitor of all the sciences, as its questions lead to the paradigm shifts upon which branches of science are founded. To limit itself to a predetermined set of rules would be to strip itself of the flexibility needed to come up with the next new thing. In other words, it is ...


9

Non sequitur I'll go off of the example in the comments, namely “One dollar” = “money” : “Nickel” = “money.” Therefore, “one dollar” = “nickel.” This is non sequitur - there's no logical reason to assume that Therefore. Or, alternatively, this could be ambiguity fallacy as this seems to be caused by (intentional?) misapplication of the symbol "=" with ...


8

It is common for beginning students of logic to read philosophical importance into the principle of explosion, but this is a mistake. The principle of explosion is merely a mathematical outcome of the way the connectives are traditionally defined in first-order logic. It doesn't reveal anything deep, however. It merely arises from the following proof: ...


7

I believe your argument strategy can be understood without thinking about analogies at all, assuming your example conveys well your general idea. I will show why and my answers will rely on that. From your example, the person claimed the strong statement of the form "the only thing that satisfies property X is Y" (namely that the only marriage that is valid ...


6

This is a question in philosophy that deals with the metaphysics of identity. A classic problem in philosophy is the Ship of Theseus and goes back to the pre-Socratics, particularly Heraclitus and his proposition that one cannot stand in the same river twice. In logic, one often draws a distinction between a name (symbol) and the thing it represents (...


6

To approach this from a slightly different angle, this concept is important in computer programming. In a lot of languages, the programmer can decide what attributes make an object "equal to" another object. For example, if you have two "People" objects represented by "first name", "last name" and "address"; you could choose to say that if the first and ...


5

In your analysis, there must be some intellectual problem with "disbelieving someone on Day 20 because they have lied every day previous to Day 20." I could split this into these parts: 1) Donald lied to me each day for 19 days straight up to yesterday. 2) Donald said something to me today, and wants me to believe it in spite of the past 19 days of lies (...


5

Another thing I would add is that proofs are built on strong axioms, but also on precise definitions. It's hard to find a precise and universally accepted definition for any complex concept in philosophy. What is life? Soul? What is a cause, an action? What is truth? Those are a much harder to define than a point, a circle or a function (not that they're ...


5

What is stopping the philosophical community from holding themselves to the same standard? The impression that the philosophers' "standards" are not sufficiently high, I think, is due to (1) the apparent lack of progress in solving philosophical puzzles in conjunction with (2) the deceiving simplicity of these puzzles. In fact, nothing stops the ...


4

This exact argument was taken up by Sally Sheldon of Kent Law School, U. of Kent, Canterbury in her 2003 article "Unwilling Fathers and Abortion: Terminating Men's Child Support Obligations?", which states that: the currently accepted grounding of child support liability (in voluntary creation of need) provides little scope for refuting the men's groups' ...


4

This answer will attempt to identify possible fallacies or false fallacies that might be applied to either the Muslim apologist or the atheists although the OP is mainly interested in identifying a fallacy committed by the Muslim. Bo Bennett's description of "Weasel Wording" may fit the description of what the Muslim apologist is attempting to do in the ...


4

This isn’t an exact fit, but the logic here is similar to the Hot Hand Fallacy. Because something has occurred frequently in the past, it in some way informs likely future events, with the assumption events will continue to transpire in the same way. It’s not a perfect fit, as the Hot Hand Fallacy specifically concerns streaks of successes making people ...


4

Cookies are not matter. Cookies are made up of matter. They are a structured form of matter. The logic you provided does not prohibit the existence of matter that existed before the epoch where these three statements hold true. The initial creation of all matter at the beginning of the universe is a complex thing. It is not clear whether "Matter cannot ...


4

I do believe you've missed the point of 'duplicate' here. 'Sameness' in this context is a fairly loose and utilitarian construct. Consider: if the temple priestess says she needs a statue of Zeus for entryway, and everyone in the village steps up to sculpt a statue of Zeus, well... the priestess still only needs (and will only use) one of those statues. The ...


4

Some texts call the fallacy of an appeal to a Nazi comparison to be "Reductio ad Hitlerum" or 'argumentum ad Hitlerum' (in this case 'Hitler' and 'Nazi' are synonymous or interchangeable). The nice thing about informal logic is that an argument made in a natural language often require us to paraphrase it so that it can be presented as an actual argument. ...


4

This would be a straight-forward case of "absence of evidence is not evidence of absence" or what is called argument from ignorance. As the article states: This represents a type of false dichotomy in that it excludes the possibility that there may have been an insufficient investigation to prove that the proposition is either true or false. Hence it is ...


3

Welcome, Elia. As usual, Conifold's arrow hits the target. I'm not aware of any philosopher of note who worked solely or mainly from a dictionary but the so-called Oxford ordinary-language philosophers of the late 1940s to 1960s believed that an examination of ordinary language could throw light on philosophical problems. J.L. Austin (1911-60), the ...


3

How often do you work on Monday nights? a) Never. b) Very rarely. c) Sometimes. d) Quite often. e) Almost always. f) Always. So the negation would be: I either work on Monday nights very rarely or never, or at least quite often. Mathematicians may use "sometimes" meaning "at least once", so to them the negation of "sometimes" would be "never". But most ...


3

This is a tu quoque, or appeal to hypocrisy, a special case of an ad hominem fallacy. The behaviour and moral character of P1 is irrelevant to the truth of the statement "B1 is morally wrong". And if B1 is morally wrong, both P1 and P2 ought to refrain from doing it. Whether one or both does in fact refrain from it changes nothing about the truth of the ...


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