A conclusion which relies on a premise which is based on the conclusion.
Example: “The Bible is the word of God – I know that because it says it in the Bible and it must be true because the Bible is the word of God.”
Denying the Antecedent
Assuming that a cause is based on the effect when there are multiple possible causes.
Example: “If you get a good degree, you’ll get a good job. If you don’t get a degree, you won’t get a good job.”
Ignoring a Common Cause
Claiming a link between 2 events, when there is a 3rd event which is likely to be the cause.
Example: “During the 60s there was a sexual revolution, because of that people are dying of AIDS.”
Cum Hoc Ergo Propter Hoc
Claiming that 2 events that occur together must have a cause-effect relationship and assuming that correlation = cause.
Example: “Smart people wear glasses, so wearing glasses must make you smarter.”
Affirming the Consequent
Assuming that there’s only one explanation for an observation you’ve made.
Example: “Marriage usually results in children, so that’s why marriage exists.”
Post Hoc Ergo Propter Hoc
The claim that because one event followed another, it was caused by it. Another cause-effect fallacy.
Example: “Since Obama became president, ISIS has become more powerful. Therefore, Obama has caused the rise of ISIS.”
Two Wrongs Make a Right
If someone is wronged, then another wrong will cancel it out
Example: “They killed 100 of our soldiers, so we need to kill 100 of their soldiers to make it right.”