IRCS Technical Reports Series

Document Type

Technical Report

Date of this Version

May 1994


University of Pennsylvania Institute for Research in Cognitive Science Technical Report No. IRCS-94-07.


Psychology considered as a natural science began as Aristotelian “physics” or “natural philosophy” of the soul. C. Wolff placed psychology under metaphysics, coordinate with cosmology. Scottish thinkers placed it within moral philosophy, but distinguished its “physical” laws from properly moral laws (for guiding conduct). Several Germans sought to establish an autonomous empirical Psychology as a branch of natural science. British and French visual theorists developed mathematically precise theories of size and distance perception; they created instruments to test these theories and to measure visual phenomena such as the duration of visual impressions. These investigators typically were dualists who included mental phenomena within nature.



Date Posted: 18 September 2006