Peirce-“Some Consequences of Four Incapacities” 228-250

Conclusion: Some Cartesian propositions like that of complete doubt, have failed to achieve certainty.  These consequences serve as a further test to that uncertainty.

“These propositions cannot be regarded as certain; and, in order to bring them to a further test, it is now proposed to trace them out to their consequences. We may first consider the first alone...” (230.)

Premises:

1.Cartesian philosophy begins with absolute universal doubt (228).

          a. we are unable to obtain knowledge from looking within ourselves (230).

          b. all knowledge is to be derived from external facts

2. Total skepticism is not a good start in the study of philosophy (228).

          a. facts previously in place are there because it was agreed upon without a reason to

             question (228).

          b. doubt should arise with reason to doubt (229).

          c. those who follow Cartesian philosophy are trying to restore beliefs previously released,

              rendering it counterproductive (228).

3. Acceptance of this proposition forces us to discard of all knowledge of the external world based on our self-consciousness (230).

           a. diversity and multiple viewpoints will be disregarded and a single mode favored to

               maintain uniformity in the study.

          

4. A single mode of action of consciousness is to be chosen to utilize logically when

              interpreting the external world (230).

           a. the chosen mode is to be reliable, unquestionable and what most closely resembles

               external facts (230).

4. This proposition limits greatly not only the knowledge we have thus far acquired but the knowledge we are still seeking.