Chapter 4: Rarity, Exteriority, Accumulation
Typical analyses of discourse take an approach dominated by 'totality and plethora.' They seek to discover a single, unarticulated meaning to which all statements in a given discourse refer (i.e., a totality). For such a totality, the set of statements (whether said or unsaid) appears as a vast plethora of possible articulations. Foucault's method, on the other hand, embraces a principle of 'rarity.' At any point in history, the range of things that could be stated far exceeds the set of statements actually made. The task, then, is to define the 'principle of rarification' that allows some statements to be made instead of others. We are not concerned with the unsaid statements themselves, but with the principles that allow only certain statements to be made. A given discursive formation is not a single, developing thing, but rather 'a distribution of gaps, voids, absences, limits, divisions.'
This rarity of statements is the 'explicit object' of the analysis of discursive formations. Rather than a single set of statements yielding an unending number of interpretations, this analysis seeks to account for statements in their finitude, taking discourse not as an oracle, but as an 'asset.' This means approaching the dispersion of statements in their 'exteriority' rather than attempting to find a secret, interior history (or a kind of historical mentality) within them. Discourse, then, must be treated as an autonomous realm, a set of statements that are 'things' which go through various transformations and appropriations. Discourse, for this method, is not simply a trace or record of something that happens somewhere else. Discourse is analyzed in its anonymity, not as the expression of an individual or collective consciousness (though it does determine the range of possible subject positions).
In its understanding of the ways in which statements and documents are preserved or accumulate, the analysis of discursive formations does not rely on the notion of cultural memory, nor on the sense that documents persist largely by chance. Instead, it understands statements to be preserved or destroyed by virtue of a network of institutions (of which the book and the library are two examples) and a set of discursive rules. The analysis does not seek to resurrect documents in hopes of re-creating the moment of their birth, but rather to describe the specific conditions of their emergence and survival. It is important, in this regard, to pay attention to variations in the form of accumulation of statements in different discourses; mathematical formulae do not accumulate in a body of knowledge in the same way that religious texts do.
Chapter 5: The Historical a priori and the Archive
Rarity, exteriority, and accumulation thus replace the respective models of totality, transcendental consciousness, and the quest for the recovery of origin. Together, this new mode of analysis approaches discourse only in its 'positivity,' only in its visible, traceable relations. It does not seek after anything hidden in or missing from or lying beneath discourse. This positivity, as the sole object of analysis, defines a limited range of things we can say about a given discourse; yet this range is not restricted by the succession of propositions, the interplay of themes, or other traditional means of understanding a discourse. The specific form of positivity that a given discourse has gives that discourse its 'condition of reality,' defining the range of statements that may be made within it. Thus, the positivity of discourse is a kind of 'historical a priori,' the 'specific form of [the] mode of being' of a set of statements. However, the a priori that is the positivity of discourse is not a separate, formal, immutable law or level of existence, but is itself 'transformable' along with specific discourses.