A start can be made in predicate logic by taking apart 'atomic' propositions and by re-phrasing what they have to say in a 'entity-has-property' way.
The constant terms a,b,c...h are used to denote entities, the predicates A,B,C...Z are used to denote properties that these entities have, and these are put together by writing the predicate first followed by the term, for example Gb.
10 Software
Hausman[2007] Logic and Philosophy Chapter 7
In predicate logic, many different styles of expression in English get cast into the same 'property-is-had-by-entity' form. For example,
6/14/07 10 Software
To start learning how to symbolize sentences using predicate logic.
Hausman[2007] Logic and Philosophy Chapter 7
There are many valid arguments which cannot be shown to be valid using sentential logic alone. For example,
Beryl is a philosopher.
All philosophers are wise.
Therefore
Beryl is wise.
There are many valid arguments which cannot be shown to be valid using sentential logic alone. For example,
Beryl is a philosopher.
All philosophers are wise.
Therefore
Beryl is wise.
12/22/05
This video is set in the context of the downloadable program, but it applies equally well in the setting of a proof applet. [It is also using a different logical system. However it will convey the principles, The video will be replaced with one suitable for this setting.]
9/4/06
This movie shows the downloadable application being used, but the manipulations are so similar to those of the web page applet that it really covers both.
This video is also using a different logical system, but it is close enough for now to illustrate the important points. [The video will be revised and replaced.]
6/21/07 10 Software
You may have derivations of your own that you wish to try. Just type, paste, or drag and drop, them into the panel, select your derivation, and click 'Start from selection'.
[Often copy-and-paste won't work directly from a Web Page; however, usually drag-and-drop will work!]
You will need to use the correct logical symbols. Here they are
F ∴ F . G ∼ ∧ ∨ ⊃ ≡ ∃ ∴
11/27/11 10Software
You now have to tools to appraise sentential arguments.
Let us run through how these might be used with two examples.
Consider the argument
If no human action is free, then no one is responsible for what they do.
If no one is responsible for what they do, no one should be punished.
Therefore
If no human action is free, no one should be punished.
First it should be symbolized
11/27/11 10Software
2/4/08