In logic and critical thinking, 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 argument takes on one of various semantically forms:
In the classical form, the arguer suggests that making a move in a
particular direction starts something on a path down a "slippery slope".
Having started down the metaphorical slope, it will continue to slide
in the same direction (the arguer usually sees the direction as a
Modern usage includes a logically valid form, in which a minor
action causes a significant impact through a long chain of logical
relationships. Note that establishing this chain of logical implication (or quantifying the relevant probabilities) makes this form logically
valid. The slippery slope argument remains a fallacy if such a chain is