Mitigated Skepticism

Skepticism is concerned with the truthfulness of human perceptions and ideas. On the level of perception, Hume was the first thinker to consistently point out the disastrous implications of the "representative theory of perception," which he had inherited from both his rationalist and empiricist predecessors. According to this view, when I say that I perceive something such as an elephant, what I actually mean is that I have in my mind a mental idea or image or impression. Such a datum is an internal, mental, subjective representation of something that I assume to be an external, physical, objective fact. But there are, at least, two difficulties inherent in ascribing any truth to such perceptions. If truth is understood as the conformity or adequacy between the image and the object, then it is impossible to establish that there is a true world of objects since the only evidence I have of an external world consists of internal images. Further, it is impossible to judge how faithfully mental impressions or ideas represent physical objects.

Hume is aware, however, that this sort of skepticism with regard to the senses does violence to common sense. He suggests that a position of complete skepticism is neither serious nor useful. Academic skepticism (the name derives from a late branch of Plato's school) states that one can never know the truth or falsity of any statement (except, of course, this one). It is, however, a self-refuting theory and is confounded by life itself because "we make inferences on the basis of our impressions whether they be true or false, real or imaginary." Total skepticism is unlivable since "nature is always too strong for principle." Hume therefore advances what he calls "mitigated skepticism." In addition to the exercise of caution in reasoning, this approach attempts to limit philosophical inquiries to topics that are adapted to the capacities of human intelligence. It thus excludes all metaphysical questions concerning the origin of either mind or object as being incapable of demonstration.