- (Hypothesis) If P, then Q
- (Hypothesis) Q
- (Conclusion) P
Here's a simple argument to illustrate the fallacy:
- If I go on a 20-mile bike ride, I will be tired.
- I am tired.
- Therefore, I went on a 20-mile bike ride.
The argument is fallacious because P need not be necessary for Q to come about.
Here's a real life illustration. P would be something like 'the Left supports the Enemy' while Q might be 'the Left is critical of the war' or 'the Enemy wins the war'.
This interview cannot be read without coming to the conclusion that the Left was aiding and abetting the enemy back then, and they are doing it again today. Period.
For lots of examples of logical fallacies (not to mention sexism, racism, and a nasty temper), read this one, too.