Difference and Repetition- Deleuze

III. The Image of Thought
This chapter takes aim at an "image of thought" that permeates both popular and philosophical discourse. According to this image, thinking naturally gravitates towards truth. Thought is divided easily into categories of truth and error. The model for thought comes from the educational institution, in which a master sets a problem and the pupil produces a solution which is either true or false. This image of the subject supposes that there are different faculties, each of which ideally grasps the particular domain of reality to which it is most suited.

In philosophy, this conception results in discourses predicated on the argument that "Everybody knows..." the truth of some basic idea. Descartes, for example, appeals to the idea that everyone can at least think and therefore exists. Deleuze points out that philosophy of this type attempts to eliminate all objective presuppositions while maintaining subjective ones.

Deleuze maintains, with Artaud, that real thinking is one of the most difficult challenges there is. Thinking requires a confrontation with stupidity, the state of being formlessly human without engaging any real problems. One discovers that the real path to truth is through the production of sense: the creation of a texture for thought that relates it to its object. Sense is the membrane that relates thought to its other.

Accordingly, learning is not the memorization of facts but the coordination of thought with a reality. "As a result, 'learning' always takes place in and through the unconscious, thereby establishing the bond of a profound complicity between nature and mind" (165).
Deleuze's alternate image of thought is based on difference, which creates a dynamism that traverses individual faculties and conceptions. This thought is fundamentally energetic and asignifying: if it produces propositions, these are wholly secondary to its development.
At the end of the chapter, Deleuze sums up the image of thought he critiques with eight attributes:

(1) the postulate of the principle, or the Cogitatio natural universalis (good will of the thinker and good nature of thought); (2) the postulate of the ideal, or common sense (common sense as the concordia facultatum and good sense as the distribution which guarantees this concord); (3) the postulate of the model, or of recognition (recognition inviting all the faculties to exercise themselves upon an object supposedly the same, and the consequent possibility of error in the distribution when one faculty confuses one of its objects with a different object of another faculty); (4) the postulate of the element or of representation (when difference is subordinated to the complimentary dimensions of the Same and the Similar, the Analogous and the Opposed; (5) the postulate of the negative, or of error (in which error expresses everything which can go wrong in thought, but only as the product of external mechanisms); (6) the postulate of logical function, or the proposition (designation is taken to be the locus of truth, sense being no more than the neutralized double or the infinite doubling of the proposition); (7) the postulate of modality, or solutions (problems being materially traced from propositions or indeed, formally defined by the possibility of their being solved); (8) the postulate of the end, or result, the postulate of knowledge (the subordination of learning to knowledge, and of culture to method. (167)