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
2/4/08
6/21/07
This video uses '&' as the logical symbol for 'and'.
6/21/07
This video uses '&' as the logical symbol for 'and'.
12/21/06
Modus Ponens (MP)
p⊃q,
p
∴
q
Modus Tollens (MT)
p⊃q,
~q
∴
~p
Disjunctive Syllogism(DS)
p∨q,
~p
∴
qor, if desired,
p∨q,
~q
∴
p
Simplication (Simp)
p.q
∴
por, if desired,
p.q
∴
q
Conjunction (Conj)
11/27/11
So that we can show certain arguments to be valid.
The focus of the course lies with the validity and invalidity of arguments. Now, invalidity can be established by counter-example (by producing an interpretation under which all the premises are true and the conclusion false, at the same time). But validity is a different matter. And the usual approach is to have rules of inference and to do derivations.
10/8/09 Under construction
<constant> ::= (['0'-'9']) |'∅'| 'U'|'{ }'
<subscript> ::= ['₁'-'₉']
<functor> ::= ['a'-'v'](< subscript >)*
<variable> ::= ['w'-'z'](< subscript >)*
<term> ::=