I’ve discussed logical fallacies in my column in the past. One such fallacy I have not touched upon is the slippery slope. By definition, a slippery slope “is a logical device, but it is usually known under its fallacious form, in which a person asserts that some event must inevitably follow from another without any rational argument or demonstrable mechanism for the inevitability of the event in question.” The slippery slope is similar to the Latin phrase post hoc, ergo propter hoc—a fallacy I have commented on in the past—which means, “after this, therefore, because of this,” and it is akin to the popular expression “opening a can of worms,” which arises from the idea of opening a can of worms just to get one worm could lead to a situation where many worms escape the jar, so one must be sure to be in great need of that one worm to justify the possible unintended consequences.
For instance, consider if I were to say that if we allow B to happen, then C will happen. C is bad, so in order to keep it from happening we cannot allow B to happen. There are a host of examples, predominantly in the media and politics, and its use has been seen in arguments from gun control to gay marriage to substance abuse.