Philosophy Stack Exchange
Philosophy Stack Exchange

Questions tagged [philosophy-of-logic]

Philosophy of logic is a branch of philosophy concerned with investigating the nature, scope and role of logic.

Philosophy of logic is the area of philosophy devoted to examining the scope and nature of logic. It is the investigation, critical analysis and intellectual reflection on issues arising in logic. The field is considered to be distinct from philosophical logic.

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If I said I had $100 when asked, but I actually had $200, would I be lying by omission?

If you had $200 cash on you right now, and I asked you if you had $100 on you, would the correct answer be yes (always/no matter what other conditions there are), no (always/no matter what other conditions there are), or it depends on the…
Yukang Jiang
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What is the difference between Law of Excluded Middle and Principle of Bivalence?

Law of Excluded Middle: In logic, the law of excluded middle (or the principle of excluded middle) is the third of the so-called three classic laws of thought. It states that for any proposition, either that proposition is true, or its negation is.…
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Why did the mid-19th century and earlier thinkers fixate on one-place predicates?

A book I'm reading mentions the following: A major barrier to the development of first-order logic had been the concentration on one-place predicates to the exclusion of many-place relational predicates. This fixation on one-place predicates had…
MWB
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Is Logic Empirical?

We use the logical system that we know from observations (empirical data) holds true in the world we live in (please correct me if I am wrong). Hence the axioms of logic we choose are themselves dependent on our observations. Does this mean that…
Suraj Jain
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What is the philosophical ground for distinguishing logic and mathematics?

I was wondering why the field of mathematics and that of logic are perceived as two distinct fields. Although could be pleased with the intuition that logic is rather meta-mathematics, still would like to know: were there any philosophers who may be…
L.M. Student
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What are the current topics in philosophy of logic?

I'm contemplating another attempt at completing my long delayed MA in Philosophy, and I need a new thesis topic. As a student I excelled in advanced symbolic logic, but my connection with academic philosophical writing has always been tenuous. …
Chris Sunami
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Why is it that the statement "All goblins are yellow" does not contradict the statement "All goblins are pink?"

From what I know, I think it has something to do with vacuous truths, but my understanding is not quite there yet.
loopzoop
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Do computers use logic?

I know we refer to computers as using logic, logic gates and the like, but is this just us ascribing human capacities to the machines? It sounds like a case of us giving more meaning to the machines than they deserve. I've read about things like…
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If you used intuitionistic logic in real life, would you not sound absurd?

Intuitionistic logic does not include the law of the excluded middle and double-negation elimination. I imagine a real-life conversation with an intuitionist might go like this: Amy said you didn't go to school yesterday. She was wrong about it…
MWB
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Why did we define vacuous statements as true rather than false?

I have been trying to understand why implications about the empty set are treated as "true". It seems to me intuitively that vacuous statements should be false. For example consider the sentence: Every element of the empty set is equivalent to a…
Charlie Parker
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What is the axiom of reducibility? And what philosophical controversies did it incite?

Trying to come to terms with basics concerning philosophy of logic, and wish to ask about some particular issue: What is in simple words the axiom of reducibility put forward by Russell? And what is its philosophical context? Among which…
L.M. Student
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Why are there two fundamental laws of logic?

We have the law of non-contradiction and the law of excluded middle, but looking at it, it seems that both of them are the same thing, or at least one of them logically implies the other. Is there a reason why we chose to say that there are two…
puffofsmoke
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Do premises need to be valid conclusions themselves?

I'm pretty new to logic. I recently purchased "A Concise Introduction to Logic" by Patrick Hurley based on reviews. So far I'm liking the book. I'm really focusing hard on the first chapter to get a good foundation, and I have a concern: if premises…
Jonathon Anderson
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How come intuitive thinking is related to constructing a proof?

I am researching Constructivism and Intuitionism. I can't understand why Intuitionism and Intuitionistic Logic are named as they are. Intuitionistic logic requires constructing a proof of every statement that is used. Therefore, for me, it feels…
NotSure
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Why was Russell discontent with Wittgenstein's view on "logic as tautologies"?

While reading Logicomix, I came across a scene that I don't quite understand. Russell: ...Logicians are creating elaborate ways to "say the same things in different words"...this "everything is a tautology" stuff smells of metaphysical bosh! This…
Dimen
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