In order to work along with the lectures, you'll find it useful to check out John Halpin's Logic Café: thelogiccafe.net/PLI/. This week we're working with Chapter Five again.
Thank you! I missed some lectures in my philosophy of logic class and this helped SO MUCH! Also I 100000% agree the mind isn't confined in the CNS or body!
@@jacksanders2611 Jack, in the example of 31:58 the student uses the "new rule of association", yet not a single rule of replacement was shown in the previous tutorials ("binged" them for every second 😅) was there any part of the lecture thats missing by any chance? Only thing remotely close taught in previous lectures was equilivancy of propositions in lecture 2..
In the example at 23:05 , If we assume A+B (or just B) and then assume ~J, we can derive ~J ---> B. You mentioned if you know something is true then it can be implied by anything. Does it also work the other way around? Could we derive B --> ~J? (along with ~J --> B)
All such derivations are conditional on the assumptions made. Thus if you assume all of A, B, and ~J, then each of those can subsequently be derived no matter what else you assume. That's because you've assumed them. But you aren't finished with a conditional proof until you back out of the assumptions, and given the way you propose running the proof, all you can back out to is "if A&B, and if ~J, then anything implies any one of the three".
In order to work along with the lectures, you'll find it useful to check out John Halpin's Logic Café: thelogiccafe.net/PLI/. This week we're working with Chapter Five again.
Thank you! I missed some lectures in my philosophy of logic class and this helped SO MUCH!
Also I 100000% agree the mind isn't confined in the CNS or body!
Hey Ellie, what were you studying? BA in philosophy?🙂
Mind 100% does reside in nervous system
Excellent. This is useful all the way from UCL (London).
Glad to know! Thanks!
@@jacksanders2611
Jack, in the example of 31:58 the student uses the "new rule of association", yet not a single rule of replacement was shown in the previous tutorials ("binged" them for every second 😅) was there any part of the lecture thats missing by any chance? Only thing remotely close taught in previous lectures was equilivancy of propositions in lecture 2..
In the example at 23:05 , If we assume A+B (or just B) and then assume ~J, we can derive ~J ---> B. You mentioned if you know something is true then it can be implied by anything.
Does it also work the other way around? Could we derive B --> ~J? (along with ~J --> B)
All such derivations are conditional on the assumptions made. Thus if you assume all of A, B, and ~J, then each of those can subsequently be derived no matter what else you assume. That's because you've assumed them. But you aren't finished with a conditional proof until you back out of the assumptions, and given the way you propose running the proof, all you can back out to is "if A&B, and if ~J, then anything implies any one of the three".