Descartes Knowledge vs. Perception Exercise
Dr. Ari Santas
Valdosta State University
Background: In the past meditations, we’ve gone from doubt, to indubitable (personal) existence, to God’s existence, to knowledge of essences. We are now in a position to ask, in what sense can we know anything about the material (corporeal) world? We already know that insofar as things are the object of pure mathematics they can be known, since these things are perceived clearly and distinctly. So, I can know essences, and therefore things, insofar as they have essences. Can I know anything beyond that? Is there any truth to things as they appear to me? Descartes retraces his steps, summarizing the previous Meditations, then outlines a theory of knowledge that shows the relationship between knowledge and perception.
Phase 1 [answer the questions, dividing the labor]
from Meditation V
1. Explain the difference between an essential and an accidental property (sometimes called primary and secondary qualities) and relate the distinction to the wax example in Meditation II.
from Meditation VI
2. What does Descartes’ example of the chiliagon illustrate? How is illustration important in his analysis of the mind and its relation to the body? Explain.
3. To what extent does Descartes think we can trust the senses by the end of Meditation VI? How can we be more sure that they aren't deceiving us, and how can we become more sure that we are not dreaming? Explain.
Phase 2 (combining groups)
4. Explain the Subject / Object Dualism Handout (next page), using your answers to 1-3.
Descartes’ Subject/Object Dualism
Ari Santas
Valdosta State University
Descartes says our essence is incorporeal, and hence only the mind itself is essential to us: only the intellect is properly ours. Things have essences too, even as corporeal. As we have seen, our intellect can seize upon the essences of things, which include extension, motion, quantity of matter. So our essence can seize upon the essences of things, and our accidental faculties seize upon accidents:
SUBJECT OBJECT
Accidents
2º qualities
(clear and distinct[1])
Imagination (Recognition /
stomach sense anamnesis)
heart Incorporeal organs Active
etc. Self Essence
Intellect Sensation 1º qualities
cause
mixed self Passive cause
(Perception)
(obscure and confused) sensuous
Corporeal properties
Self
The Psycho-Physical Self The External World
Just as Descartes is a dual being, so are the objects of perception (which themselves stand in dualistic opposition to the knowing subject). Note that the essential side of Descartes knows the essence of the thing while his accidental side “knows” the accidents of the object.
[1] Early Modern Texts has decided to translate Descartes’ famous ‘clair et distinct’ phrase as ‘vivid and clear’ instead of the typical rendition ‘clear and distinct.’