The Chiasm and Reversibility

1. Defining the Chiasm: Structure of Mediation

Before turning to Merleau-Ponty's dense primary text, let's establish a clear, orienting definition of the chiasm from a reliable secondary source.

This reading gives us several crucial coordinates:

• Chiasm (Χ): A crisscrossing structure. Etymologically, it can refer to the crossed arrangement of optic nerves (physiological) or a literary device where structures are repeated in reverse order (AB:BA).
• Structure of Mediation: For Merleau-Ponty, the chiasm is the structure that mediates between terms we traditionally see as opposed (subject/object, sentient/sensible), combining their unity-in-difference with a sense of reversal and circularity.
• Three Consequences of Self-Touch:
  1. The body is an "exemplar sensible," proving the kinship between subject and object.
  2. The relationship is reversible, like an "obverse and reverse."
  3. The sentient and sensible never perfectly coincide; they are separated by a gap (écart).

You can see how this structural concept, the chiasm, formally accounts for the dynamic process of reversibility and the écart that we studied in the last lesson.

2. The Form of Intertwining in Merleau-Ponty's Text

Now, let's see how Merleau-Ponty himself describes this structure. He uses a series of powerful metaphors to articulate the form of this intertwining, moving beyond the simple idea of two separate things interacting.

In this rich passage, Merleau-Ponty builds a precise picture of the chiasm:

• Not Two Layers: He rejects thinking of the body as having a "sensible" layer and a "sentient" layer. This would be to fall back into a flattened, dualistic view.
• Obverse and Reverse: A better metaphor is the obverse and reverse of a single coin or page—two faces of one and the same thing, inseparable and mutually defining.
• Circular Course: He describes a single movement that has two phases, like a circular path. This captures the dynamic aspect of reversibility within a single unified structure.
• Reciprocal Insertion: This leads to the core of the chiasm: a "reciprocal insertion and intertwining of one in the other." The seer is in the visible world, but the visible world is also subtended by the seer's body. They are not contained within each other like boxes; they are mutually enfolded.
• A Couple More Real Than Either: This is a striking formulation. The chiasmatic relationship between seer and visible (or toucher and tangible) forms a "couple" that is ontologically more fundamental than either term taken in isolation. This "couple" is the basic reality, not the two individual poles.

This is the ontological structure that makes reversibility possible. The touching hand can become the touched hand because they are already two poles of a single chiasmatic "couple," two moments in one "circular course."

3. The Hiatus: The Center of the Chiasm

We've established that the chiasm is the "X" structure where two lines (sentient/sensible) intertwine. Given your mathematical background, you know that the most interesting part of an "X" is the point of intersection. In Merleau-Ponty's philosophy, this intersection is the écart, the gap we discussed last lesson.

Let's revisit the passage where he describes this gap, but this time reading it as a description of the chiasm's central point.

This "hiatus" or "spread" is the very heart of the chiasm. It is not an ontological failure or a simple absence. It is the structural divergence that holds the two terms apart, allowing them to be distinct, while simultaneously being the hinge that joins them into a single system.

Think of the "X": the two lines are distinct everywhere except at the center, yet it is the center that defines their relationship. For Merleau-Ponty, this center is a dynamic separation-and-connection. It is the "zero of pressure between two solids that makes them adhere to one another." This is the structure that allows for the process of reversibility, a process that is always a near-miss, a perpetual exchange across a tiny but unbridgeable gap.

4. The Generalization of the Chiasm

Merleau-Ponty does not confine this structure to the body's self-experience. He elevates it to a fundamental principle of Being itself. The chiasm describes the intertwining of self and other, and even of language and meaning.

• Intercorporeality: The chiasm extends between bodies. As Merleau-Ponty famously states in a passage we read previously (p. 142), "The handshake too is reversible." When I shake another's hand, I can feel myself being touched as I touch. Our bodies form a temporary chiasmatic couple.
• Language and Thought: He applies the same logic to meaning. In another passage (p. 154), he describes "a reversibility of the speech and what it signifies." The meaning of a phrase and its sonorous, physical presence are not two separate layers. They are intertwined in a chiasm. The meaning is the "other side" of the sound, and vice versa.

As the SEP article notes, we should picture Merleau-Ponty's universe as a "proliferation of chiasms" at all levels, from perception to sociality to language and thought.

Conclusion

Today we have put a name and a form to the dynamic process of reversibility. The chiasm is the fundamental ontological structure that accounts for the intertwining of seemingly opposite terms.

Key Takeaways:

• The Chiasm (Χ): An "X"-shaped structure of crisscrossing, reversal, and intertwining that mediates between terms like sentient/sensible and subject/object.
• The Structure of Reversibility: Reversibility is the process that unfolds upon the pre-existing structure of the chiasm. My hands can reverse roles because they are already held in a chiasmatic relationship as two "leaves" of one body.
• The Écart as Hinge: The gap, or écart, between the two terms is the central point of the chiasm. It is not a void but a productive divergence that both separates and binds the terms together.
• A General Principle: The chiasm is not limited to self-touch. It is a general ontological structure describing the relationship between the body and the world, self and other, and even language and meaning.

Preview of the Next Lesson:

We have now defined Flesh as the elemental stuff of being, reversibility as its dynamic process, and the chiasm as its underlying structure. In our next lesson, we will ask: what is the nature of the reality described by these concepts? Merleau-Ponty gives it a name: 'wild Being' (être sauvage). We will explore what this term means and how it functions as the ultimate ground of his late ontology.