6

It would be worthwhile distinguishing between a conditional sentence in the object language and a conditional in the metalanguage. Some deductive arguments have a conditional in the object language, e.g. those of the form modus ponens or modus tollens. Some arguments do not, e.g. those of the form conjunction elimination, disjunction elimination, etc. But ...


6

I suppose you are looking for reasons not to identify properties to sets. (1) A set is a particular ( an abstract particular) , but properies are often considered as universals . (2) A property is something an object possesses, shares; it is also the case for a set? I mean, could I say that an apple " possesses" the set of red objecs? (3) Suppose ...


6

The school board's negative phrasing like "found no evidence" or "hasn't recommended" suggests an intention to pass absence of evidence for evidence of absence. The relationship between the two is complex and sometimes subtle, see When is absence of evidence not evidence of absence? It can be plausible when the evidence should have been ...


5

Short Answer Technically speaking, the intentional use of misleading language is more in the domain of rhetoric than logic and is known as sophistry. A fallacy is generally considered any persuasive argument of bad form. See What is the philosophical term used to describe flawed logic? for more details on what constitutes a fallacy. Long Answer Once one ...


4

It's a good question. I believe one could say the same of analytical philosophy with its emphasis on logic. This could be studied ahistorically, and if you understood Frege you would not have much trouble with Aristotle, or at least his logic, though I hasten to add, those are not my areas of thoroughly amateur reading. Likewise, you could go on to study ...


4

Short Answer Philosophy is almost completely conducted in natural language, and the study of the origins of the "why's" of natural language are a concern of the philosophy of language. What these philosophers agree on is that metaphors are used to communicate thoughts. In fact, some philosophers believe there is a language of thought. Ultimately, ...


4

To my knowledge, there is, regrettably, no textbook-style source on the theory of definition. However, Definitions and Definability: Philosophical Perspectives (edited by J. H. Fetzer et al, Springer, Synthese Library, 1991) is quite accessible to the novice and freely available from Springer. As it is for many topics in philosophy, I would recommend you to ...


4

I think you are simply mistaking Yablo's nomenclature here. He is using the arrow symbol → to denote a counterfactual conditional, or perhaps some general conditional, not material implication. For example, note that in footnote 22, p. 176, he says "I assume that π → S is false iff π → ~S is true." This would not be true of material implication, ...


3

Meinong's Ontology would be a good starting place to research. I will try my best to explain, but my understanding is still shakey. Meinong's Ontology divides up our system of being into three different classes: Absistence, Subsistence and Existence. Absistence includes every possible object or idea you can think of. This would include unicorns, mythical ...


3

The point of "the world is the totality of facts, not of things" is exactly that facts are over and above things, the result of human mind interacting with things, logical atoms being the smallest units of such interaction. In other words, he is making the same point as the OP, see Wittgenstein on facts and objects: the metaphysics oftheTractatus ...


3

The sentences continue to make sense in theory, but beyond some point it just becomes too much for our human working memory to track. From this article: Now try the fifth sentence: The malt that the rat that the cat that the dog worried killed ate lay in the house that Jack built. Are you still following me? That last example is perfectly grammatical, but ...


3

You're asking if the inference from There is one A to There are some A's is a logical fallacy. The answer is no, but there is a reason why some seems to mean more than one. First, note that in your Example 1 the parent can seem to contradict the child even if the parent agreed that there was more than one time: Child: Sometimes you forget to pick me up from ...


3

This is really a question about the definition of "rational person." Rationality can be subdivided into a number of different types or categories of reasoning, which include: Deductive reasoning (drawing logical inferences from rigorous application of the rules of classical logic). Inductive reasoning (inferring that a general statement is "...


3

Imprecise language is getting in the way You interpret the meaning of "Unicorns don't exist" as "there's this thing called a unicorn which has the property of not existing" which you have properly identified as being incorrect. However, consider this interpretation: "Unicorns don't exist" meaning "The set of all unicorns ...


3

Special pleading. Special pleading (Law) a pleading that alleges new facts that offset those put forward by the other side rather than directly admitting or denying those facts (Law) a pleading that emphasizes the favourable aspects of a case while omitting the unfavourable Their formulation avoided the admission that one obvious possibility not excluded ...


3

Your question is not entirely clear to me. Yablo claims that the truth conditions of simple sentences s containing definite descriptions may change depending on whether or not the presuppositions triggered by the descriptions are satisfied or not. If they are not satisfied, then the sentence s is true iff the counterfactual p > s is true, where p is the ...


3

The OP question is somewhat complicated by the imperative mood, but I do not believe that the logic of imperatives or deontic logic (see Hansen, Is there a Logic of Imperatives? for an overview) are at fault for bringing about the counterintuitive result. For the purposes of this example we can straightforwardly interpret imperatives as descriptions of a ...


2

The most voted answer asserts that "mathematical facts are timeless". However, it is my opinion that in order to assert this you need to have a Platonic view of mathematics: indeed, if they are timeless, then they must exist independently of your knowledge, and in particular what is true and false in mathematics is pre-determined regardless of ...


2

The concept of definition is broad. So broad in fact, that you can bring to life a whole ontological realm with definitions. This is the case with set theory and all the mathematical objects you can define upon set theory. The abstract object of set is implicitly defined by the theory's axioms. Further objects are defined with explicit and contextual ...


2

You might refer to Wittgenstein's problem of rule following (Regelfolgenproblem): No matter on how many uses of a word two people agree, they cannot be sure they will agree on any further uses. The reason is that there are no rules that would govern the use of a word in a natural language. Hence, they cannot be following the same rule. The lack of rules ...


2

It comes down to how you interpret the meaning of the sentence "x has radius y". (As has been pointed out in the comments, one can meaningfully define the radius of a triangle, but for the sake of argument we take it be defined only for circles.) Consider the following two interpretations: (1) x is a circle that has radius y. (2) x is a circle that ...


2

Regarding the example, we can apply Russell's analysis of definite descriptions to the statement "the Radius of Triangle has lenght 6" (of the general form "the F is G") : exists x ((Rad(x,T) and for all y (Rad(y,T) → x=y)) and x=6). Thus, mimicking Russell's example regarding "the current Emperor of Kentucky is gray", if we ...


2

As self-reports, all except 2 are simply true, assuming accurately reported (and you aren't lying.) But not "moral statements" at all. And 2 is a moral statement only in the unlikely case that you are God or some other presiding moral authority. In a deontic sense, at least, moral statements should be univeralizable or at least general, so cannot ...


2

Moral statements are prescriptive statements uttered within an interpersonal context. If they are descriptive of anything, they are descriptive of socially defined norms or ideals. I mean, consider a man trapped alone on a desert island. For that man, 'lying' is neither moral nor immoral; it serves no end and has no purpose. He might lie to himself, I ...


2

Short Answer 'Theory' is used by both scientists and philosophers, and the nature of space and time is still very much the domain of the philosophy of science, as opposed to science proper. Long Answer According to the Online Etymology Dictionary, the vernacular 'theory' comes from Latin: 1590s, "conception, mental scheme," from Late Latin theoria ...


2

The key difference is that mathematics is linear, it progresses forward, and each new step builds on the last. Philosophy is cyclical, it returns to certain topics and modes of thought repeatedly. Accordingly ancient philosophy is often of current interest and relevance in a way that is rarely true of ancient science or mathematics (except the the extent ...


2

The philosophy in which falsifiability, or its close relative verifiablilty, is the criterion for meaning is known as logical positivism. It was all the rage in the mid-twentieth century. The verification principle states that no statement has any meaning unless it is, at least in principle, verifiable. The problem is that the verification principle is ...


2

Quoted from: Jennifer Cook O’Toole, "The Asperkid’s (Secret) Book of Social Rules" (Jessica Kingsley Publications, 2012) page 137 Eager to share some juicy gossip, the man asked if Socrates would like to know the story he’d just heard about a friend of theirs. Socrates replied that before the man spoke, he needed to pass the “Triple-Filter” test. ...


2

It is not clear that, whatever Ruloff's ideas about language they were actually formulated in book form - printed book or complete manuscript. Nothing appears to have been publshed under his name. He was the subject of a book: Life, trial and execution of Edward H. Ruloff : the perpetrator of eight murders, numerous burglaries and other crimes; who was ...


2

This is one of the horns of Munchausens trilemma. I would follow Hofstadter idea of 'tangled hierarchies' & strange loops, to say language and logic are systems within a looping hierarchy, with niether a fundamental grounding nor end point or final conclusions (final vocabulary). Instead, the whole system of system is verified by self-coherence, in ...


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