@SteveShaw008 Mmm... "John is" is not a propositional claim. Nor is "wearing a red coat" or "stolen a jeep". Only when you put a subject term and a predicate term together do you get a proposition that makes an assertion that could be true or false (which is the defining characteristic of a proposition).
@PhilosophyFreak That should read: "John is wearing a read coat" and "John has stolen a jeep," two propositional claims. "John is" could mean "John exists," another propositional claim. Otherwise, you risk making P. Coffey's mistake, one of several that Wittgenstein listed in his review of Coffey's book (1913): "III [6] He confounds the copula is with the word is expressing identity. (The word is has obviously different meanings in the propositions—Twice two is four and Socrates is mortal.)"
@xXHellScreemXx Yep. At least, computer programming is usually based on Boolean logic, and Boolean logic is just a form of propositional logic. DeMorgan's rules, for example, are basic theorems of propositional logic, but every computer science student knows them.
Nice video, I am studying this and am only confused on one thing, syntactic and semantic sequents, when something syntactically and semantically entail another, I don't get that.
@meeene4 That is a tricky distinction. Basically, semantics is about meaning (which in this case is about whether a given proposition is true or false), and syntax is just about the formal rules for manipulating symbols. Semantic entailment involves questions like "If A is true and B is true, does C have to be true?". Syntactic entailment is about what you can derive from the inference rules. There's a close overlap but they are distinct concepts of entailment.
nice visual and great fresher; hope there are more and hope it breaks down how to breakdown real world arguments and to build some others (e.g., in research papers)
@ 2:06. "John is" is also a propositional claim, that is, in addition to "wearing a red coat" and "stolen a jeep."
SteveShaw008 2 months ago
@SteveShaw008 Mmm... "John is" is not a propositional claim. Nor is "wearing a red coat" or "stolen a jeep". Only when you put a subject term and a predicate term together do you get a proposition that makes an assertion that could be true or false (which is the defining characteristic of a proposition).
PhilosophyFreak 2 months ago
@PhilosophyFreak That should read: "John is wearing a read coat" and "John has stolen a jeep," two propositional claims. "John is" could mean "John exists," another propositional claim. Otherwise, you risk making P. Coffey's mistake, one of several that Wittgenstein listed in his review of Coffey's book (1913): "III [6] He confounds the copula is with the word is expressing identity. (The word is has obviously different meanings in the propositions—Twice two is four and Socrates is mortal.)"
SteveShaw008 2 months ago
@SteveShaw008 That's good, I wasn't thinking along those lines! (Neither would most intro texts, though, so I don't feel too bad :) )
PhilosophyFreak 2 months ago
isnt that computer science?
xXHellScreemXx 7 months ago
@xXHellScreemXx Yep. At least, computer programming is usually based on Boolean logic, and Boolean logic is just a form of propositional logic. DeMorgan's rules, for example, are basic theorems of propositional logic, but every computer science student knows them.
PhilosophyFreak 7 months ago
Nice video, I am studying this and am only confused on one thing, syntactic and semantic sequents, when something syntactically and semantically entail another, I don't get that.
meeene4 8 months ago
@meeene4 That is a tricky distinction. Basically, semantics is about meaning (which in this case is about whether a given proposition is true or false), and syntax is just about the formal rules for manipulating symbols. Semantic entailment involves questions like "If A is true and B is true, does C have to be true?". Syntactic entailment is about what you can derive from the inference rules. There's a close overlap but they are distinct concepts of entailment.
PhilosophyFreak 7 months ago
nice visual and great fresher; hope there are more and hope it breaks down how to breakdown real world arguments and to build some others (e.g., in research papers)
onoringo 1 year ago
good stuff
tolsonw 2 years ago
this is great, thank you
ilkucuk 2 years ago