You should now Launch Deriver and do the 4 exercises of Predicate Exercise 1 (Predex1).
It is usual to analyse an argument using only propositional logic or only predicate logic-- you do not mix up the two levels on one argument. We now move on to predicate logic...
Make sure Predicate Level is chosen under the Semantics Menu (the program can analyse at either level, but it needs to know what you want to do).
The program knows of three names and has itself adopted the following
conventions regarding them
The program knows of two intransitive verbs and has itself adopted the following conventions regarding them
Form a view as to how the program will symbolize the following propositions, then ask it to do so by selecting and copying the proposition and clicking To Symbols. (Either a) select and copy in your Web Browser and click To Symbols in Deriver, or b) select and copy in your Web Browser, paste it into Deriver, select in Deriver (no need to copy) and click To Symbols in Deriver, or c) select and copy this whole exercise in your Web Browser, paste it into Deriver, select the individual English sentence in Deriver (no need to copy) and click To Symbols in Deriver.) When you have symbolized the propositions, ask the program to translate them back by selecting each symbol and clicking To English.
Symbolize:
a) Arthur studies.
b) Charles thinks.
c) Beryl studies.
d) Arthur studies and Beryl thinks.
e) It is not the case that Charles studies.
f) Charles studies only if Arthur studies.
g) Arthur does not thinks. (*see note*)
h) Arthur and Charles thinks.
i) Neither Beryl nor Arthur thinks.
j) Beryl studies and thinks.
k) Both Beryl and Charles both thinks and studies.
l) Neither Beryl nor Arthur neither studies nor thinks.
(*Note that English grammar is a context sensitive grammar and this means that no computer program can deal with it correctly in its entirety. This program makes simplifications and trims English down to a basic core 'near-English' which a computer can manage. For example, one simplification is not paying a lot of attention to having verbs agree properly with their subjects-- for the computer we write 'John goes' and 'John and Jill goes'. No doubt you will seized with a warm and humourous feeling when reading some of these sentences (all students of logic experience this at some time or another). The point of it is to convey how grammatical structure transforms into logical structure and the intermediate near-English helps in this . *)
Often you would have to chose the conventions (or dictionary) that you use for translation. In this exercise you must choose how you are going to symbolize the names and intransitive verbs.
The program knows of the three names and two verbs above. But the program can be taught more.
Tell the program of your conventions by selecting
remember name (<english in here>) <small letter in here>
remember iverb (<english in here>) <capital in here>
and clicking Do Command under the Actions menu.
Then ask the machine to translate back and forward for you.
First tell of your conventions, the first command is laid out for you
remember name (David) d
remember name (Ena) <small letter here>
remember iverb (relaxes) R
remember iverb (works) <capital here>
then symbolize
a) David relaxes.
b) Ena relaxes.
c) Ena works if and only if David relaxes.
d) If David works or relaxes then Ena neither works nor relaxes.
The program knows of the aforementioned three names.
The program knows of three adjectives and has itself adopted the
following conventions regarding them
Form a view as to how the program will symbolize the following propositions, then ask it to do so by selecting the proposition and clicking 'To symbols'. When you have symbolized the propositions, ask the program to translate them back by selecting each symbol and clicking 'To English'.
Symbolize:
a) Arthur is angry and Charles is cheerful.
b) Beryl is bold.
c) Charles is not angry.
d) If Charles is not angry then Arthur is cheerful.
e) Beryl is neither cheerful nor angry.
f) Arthur is angry and cheerful and Charles is cheerful.
In this exercise you must choose how you are going to symbolize the adjectives. Tell the program how you are going to do it by selecting
remember adjective (<english in here>) <capital in here>
and clicking Do Command.
Then ask the machine to translate back and forward for you.
First tell of your conventions
remember adjective (kind ) <capital-here>
remember adjective (lively) <capital-here>
then symbolize
a) Charles is lively or Beryl is kind.
b) Beryl is kind if and only if Arthur is kind.
c) Arthur is both kind and lively.
d) If Charles is kind then Arthur is kind and lively.
e) Beryl is lively or Charles is lively or kind.