Also Known as: The Camel's Nose.
Description of Slippery Slope
The Slippery Slope is a fallacy in which a person asserts that some event must inevitably follow from another without any argument for the inevitability of the event in question. In most cases, there are a series of steps or gradations between one event and the one in question and no reason is given as to why the intervening steps or gradations will simply be bypassed.
This argument states that should one event occur it will initiate a chain of events culminating in an undesirable event later. There is no proof made that the undesirable events are caused by the first event.
Definition: In order to show that a proposition P is unacceptable, a sequence of increasingly unacceptable events is shown to follow from P. A slippery slope is an illegitimate use of the "if-then" operator.
This "argument" has the following form:
Event X has occurred (or will or might occur).
This sort of "reasoning" is fallacious because there is no reason to believe that one event must inevitably follow from another without an argument for such a claim. This is especially clear in cases in which there is a significant number of steps or gradations between one event and another.
"You can never give anyone a break. If you do, everyone will walk all over you."
"We've got to stop them from banning pornography. Once they start banning
one form of literature, they will never stop. Next thing you know, they will
be burning all the books!"