In SAT/SMT by Example i described IMPLY operation, often written as "=>": Ctrl-F "IMPLY constraint". Also, in Wikipedia.
"P => Q" is like:
Q = ? if P==True: Q=True
Important: you don't know state of Q before. Q modified to True only if P is True.
Now let's read Wikipedia about formal fallacy:
Any argument that takes the following form is a non sequitur #If A is true, then B is true. #B is true. #Therefore, A is true.
But we know that if A => B, opposite is (B => A) not true.
Another common non sequitur is this: #If A is true, then B is true. #A is false. #Therefore, B is false.
The B 'global variable' could be set before.
Affirming a disjunct is a fallacy when in the following form: #A or B is true. #B is true. #Therefore, A is not true.*
If P => Q, state of Q do not influence state of P.
Also, from Wikipedia about argument from fallacy:
If P, then Q. P is a fallacious argument. Therefore, Q is false.
P doesn't influence Q if P=False.
List of my other blog posts.
Yes, I know about these lousy Disqus ads. Please use adblocker. I would consider to subscribe to 'pro' version of Disqus if the signal/noise ratio in comments would be good enough.