Some basic statements from my Logic and Reasoning in CS class
1 June 2026 · Liam
then
No, countermodel:
then holds but doesn’t
if and then
Proof by contradiction: If this is false the first part needs to hold, while the second doesn’t. So and need to be and , because of .
then for the first part to hold, as , also has to be . However that means , which will always be false.
There is no interpretation so that this statement is wrong. the statement is true
if then
P.b.c.: We need an interpretation i.e. and .
However then is never true, but is always true.
does not hold.
There is no interpretation so that the statement is wrong. the statement is true