In philosophy, logic is the formal study of reasoning. We’re constantly told to “think logically,” meaning we should think critically, basing conclusions on evidence and reason. The trouble is, our human brains come to a lot of illogical conclusions.
There are dozens of fallacies, faulty generalizations, and red herrings that can trip us up. Maybe you remember this classic from the SATs: “If A, then B,” which means whenever A is true then B is also true. Seems pretty straightforward. Unfortunately, our brains are so smart that they can get ahead of themselves and tell us things like, “Well if that’s the case, I guess if A is not true, then B must not be true.” You might think that, but you’d be wrong. Our premise is “if A, then B.” We have no idea what happens to A if B is not true or for that matter what B’s status is when A is not true. That’s called the “fallacy of the inverse.”
Another common fallacy is “fallacy of the single cause,” or when we make the illogical assumption that an outcome can only have one cause. Then there’s the times we decide that there are only two possible choices in a given situation when there may be other alternatives. That’s called a “false dilemma,” which we’ve all probably experienced at work one time or another. The fallacy that correlation means causation is so common that it has spawned a very funny website (and now book) called Spurious Correlations. Here’s one:
To be honest, one would have assumed Nicholas Cage films to be responsible for more drownings. but you get the point. Our insanely smart, really stupid brains make all kinds of critical thinking errors. Here are some websites that might help: From Tech Republic, 10 tips to sharpen your critical thinking skills , then there’s this mini course on how to identify logical fallacies, and from 2011, this piece by Prof. Chris MacDonald on critical thinking and business ethics.