ABSTRACT

The Essays on tbe Intellectual Powers is a mature work reflecting a lifetime of thought and inquiry. There is overlap between this work and the Inquiry, Both contain an attempt to refute the ideal theory, a theory of perception as a response to signs, and an appeal to first principles and common sense. There are also important differences. The later work is a systematic study of the faculties of the human mind, of reason, memory, conception, and taste as well as perception. There is, however, a more important shift in emphasis from those processes that are original and irresistible to those that are acquired and reflective. From a twentieth-century perspective, the shift may be considered to be a shift from the study of the automatic information processing of the perceptual input systems to a study of the more plastic operations of the central processing system. The subjects of inquiry are further expanded beyond an investigation of the human faculties to ontology and the philosophy of language. Perhaps, the primary difference between the Inquiry and the Essays is the emphasis on artificial language in the later work. A theory of human language and of general conceptions is developed. Moreover, the features of language are appealed to as an indicator of common opinion and hence of the first principles of common sense. Those principles are explicitly and systematically articulated. The result is a philosophical system concerning the intellectual powers of the human mind.