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OpenLogicProject / OpenLogic

An open-source, customizable intermediate logic textbook
http://openlogicproject.org/
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Separate propositional logic and first-order logic #77

Closed rzach closed 7 years ago

rzach commented 8 years ago

Currently the "book" goes right into first-order logic. People might want to start with propositional logic, especially if it's for a course that continues wih propositional logic only (say, modal, intuitionistic logic). So we should separate out the propositional from the first order (quantifiers, identity) material in the chapters on proof systems so they can be included in a part on propositional logic (to be written/expanded: a first draft is in the axiomatic-deduction branch https://github.com/OpenLogicProject/OpenLogic/tree/axiomatic-deduction )

nicolewyatt commented 8 years ago

I see the appeal of having propositional logic separate in the cases you mention, but for those classes that are doing the whole thing, having it separate is pedagogically unsatisfying. Is there any way we could keep both options, or is the tagging just too hard?

On December 10, 2015 at 7:41:24 AM, Richard Zach (notifications@github.commailto:notifications@github.com) wrote:

Currently the "book" goes right into first-order logic. People might want to start with propositional logic, especially if it's for a course that continues wih propositional logic only (say, modal, intuitionistic logic). So we should separate out the propositional from the first order (quantifiers, identity) material in the chapters on proof systems so they can be included in a part on propositional logic (to be written/expanded: a first draft is in the axiomatic-deduction branch https://github.com/OpenLogicProject/OpenLogic/tree/axiomatic-deduction )

— Reply to this email directly or view it on GitHubhttps://github.com/OpenLogicProject/OpenLogic/issues/77.

Cubesoup commented 8 years ago

I would like to point out that a further advantage of separating the topics is the Cartesian closed category / simply typed lambda calculus connection to (intuitionistic) propositional logic, which the quantifiers make much more confusing. On 15 Dec 2015 3:56 pm, "Nicole Wyatt" notifications@github.com wrote:

I see the appeal of having propositional logic separate in the cases you mention, but for those classes that are doing the whole thing, having it separate is pedagogically unsatisfying. Is there any way we could keep both options, or is the tagging just too hard?

On December 10, 2015 at 7:41:24 AM, Richard Zach (notifications@github.com mailto:notifications@github.com) wrote:

Currently the "book" goes right into first-order logic. People might want to start with propositional logic, especially if it's for a course that continues wih propositional logic only (say, modal, intuitionistic logic). So we should separate out the propositional from the first order (quantifiers, identity) material in the chapters on proof systems so they can be included in a part on propositional logic (to be written/expanded: a first draft is in the axiomatic-deduction branch https://github.com/OpenLogicProject/OpenLogic/tree/axiomatic-deduction )

— Reply to this email directly or view it on GitHub< https://github.com/OpenLogicProject/OpenLogic/issues/77>.

— Reply to this email directly or view it on GitHub https://github.com/OpenLogicProject/OpenLogic/issues/77#issuecomment-164916932 .

rzach commented 8 years ago

I'm planning to separate & tag. -R

On 2015-12-15 03:56 PM, Nicole Wyatt wrote:

I see the appeal of having propositional logic separate in the cases you mention, but for those classes that are doing the whole thing, having it separate is pedagogically unsatisfying. Is there any way we could keep both options, or is the tagging just too hard?

On December 10, 2015 at 7:41:24 AM, Richard Zach (notifications@github.commailto:notifications@github.com) wrote:

Currently the "book" goes right into first-order logic. People might want to start with propositional logic, especially if it's for a course that continues wih propositional logic only (say, modal, intuitionistic logic). So we should separate out the propositional from the first order (quantifiers, identity) material in the chapters on proof systems so they can be included in a part on propositional logic (to be written/expanded: a first draft is in the axiomatic-deduction branch https://github.com/OpenLogicProject/OpenLogic/tree/axiomatic-deduction )

— Reply to this email directly or view it on GitHubhttps://github.com/OpenLogicProject/OpenLogic/issues/77.

— Reply to this email directly or view it on GitHub https://github.com/OpenLogicProject/OpenLogic/issues/77#issuecomment-164916932.

Richard Zach ...... http://www.ucalgary.ca/rzach/ Professor, Department of Philosophy University of Calgary, Calgary AB T2N 1N4, Canada

rzach commented 7 years ago

Ok, I've done this. It's not very intrusive, basically just separating things into more sections. Material can now be (I think) reused without quantifier easily. Exception: the soundness proof. I'll leave that for another day.