Intentional Arc

Merleau-Ponty's name for the unity that underlies perception, intelligence, memory, projection, desire, and motility — the "vector" that binds the life of consciousness into a single intending-of-the-world. Introduced in Part One Ch III.j of Phenomenology of Perception as the unity that goes "limp" in the Schneider case, and that therefore makes visible only when it fails.

Key Points

  • The definition: "The life of consciousness — epistemic life, the life of desire, or perceptual life — is underpinned by an 'intentional arc' that projects around us our past, our future, our human milieu, our physical situation, our ideological situation, and our moral situation, or rather, that ensures that we are situated within all of these relationships. This intentional arc creates the unity of the senses, the unity of the senses with intelligence, and the unity of sensitivity and motricity. And this is what 'goes limp' in the disorder" (PhP, p. 137).
  • The argument from unity: Schneider's impairment is not a sum of elective losses (in vision, in movement, in memory, in thought). It is a single collapse that affects all of these together. Something must unify them for a single collapse to be possible — and that something is the intentional arc.
  • Not a "searchlight": MP's own reservation: "the comparison to a searchlight is not a good one, since it takes for granted the given objects upon which intelligence projects its light, whereas the core function we are speaking of here — prior to making us see or know objects — first more secretly brings them into existence for us" (p. 137). The arc does not illuminate a pre-given world; it projects the world it inhabits.
  • Borrowed term, MP doctrine: The phrase "intentional arc" is borrowed from an earlier work by Buytendijk and Plessner; MP takes it to name the unity his analyses of perception, motility, memory, and sexuality have been circling. The concept is MP's; the term is imported.
  • The structural form of existence: The arc is not just an empirical fact about this particular subject; it is the structure of what it is to be a subject at all — to be "situated within" past, future, milieu, physical situation, ideological situation, moral situation. To lose the arc is to lose the situation-hood of one's existence.

Details

How the Arc Is Discovered

MP's argumentative path to the intentional arc is a progressive demonstration that Schneider's apparently scattered symptoms — defective motor planning, concrete-only movement, narrowing of attention, loss of temporal horizon, flat affect, impoverished speech — are all one symptom. Each of these had been the subject of its own section, and in each MP had shown that neither empiricism nor intellectualism can explain the symptom atomistically. Section III.j draws the cumulative lesson: "Thus, all of Schneider's disorders can be reduced to a unity, but this is not the abstract unity of the 'representation function.' Schneider is 'bound' to the actual, and he 'lacks freedom,' he lacks the concrete freedom that consists in the general power of placing oneself in a situation" (p. 137).

The phrase "bound to the actual" is the key. Schneider is not diminished in capacity (he does as much work at the wallet factory as 75% of the normal workers). He is diminished in possibility. Possibility is exactly what the intentional arc underwrites: "we discover beneath intelligence and beneath perception a more fundamental function: a vector moving in every direction, like a searchlight, by which we can orient ourselves toward anything, in ourselves or outside of ourselves, and by which we can have a behavior with regard to this object" (p. 137).

"Projects around us our past, our future..."

The arc is temporal and axiological as well as spatial. It "projects around us our past" — which is why Schneider's past appears to him only as the "shriveled up continuations of the present" (p. 137). It "projects our future" — which is why Schneider cannot project himself into possible situations and cannot live language that expresses merely possible scenarios. It projects "our human milieu, our physical situation, our ideological situation, and our moral situation" — the six dimensions of the projection locate the arc at the intersection of embodiment and culture.

This enumeration is not incidental. It is the field of being-in-and-toward-the-world broken down into its structural dimensions. The arc is MP's name for how these dimensions are bound together into a single field of intelligibility. Break one strand, and all strands go slack.

The Unity of the Senses

One of the arc's specific accomplishments is "the unity of the senses." MP devotes Part Two Ch I to the argument that the senses are not separate streams synthesized by an intellectual act but are already united in the pre-personal body — synesthesia is the rule, not the exception. The intentional arc is what accomplishes this unity. The analogical reach across sensory modalities that allows us to perceive a shape as both seen and touched — without ever having paired the two modalities explicitly — is the arc at work.

Similarly the "unity of sensitivity and motricity": what is given to the senses is given as something to be handled, walked around, grasped. There is no pre-motor perception in normal experience; the arc is what ensures that perception is already motor and that motion is already perceptual. The Schneider case makes this visible because the patient fails this unity first: he can see and he can move, but sight no longer solicits motion, and motion no longer orients sight.

The Arc as Limit Concept

A crucial methodological point: the arc is not observable in normal functioning. A functioning intentional arc is what lets anything be observable at all — it is the condition under which a world shows up. You cannot catch the arc in the act of arcing; you can only see it retrospectively, from its damage.

This is why Part One's structure is so relentlessly pathological. MP is not collecting curiosities; he is using the only method by which a transcendental structure that is always already at work can be brought into view. The intentional arc stands to Schneider's impairment as the Kantian forms of intuition stand to the impossibility of imagining their absence — except that MP's "impossibility" is shown empirically, through a subject in whom the arc has actually gone slack.

Connections

  • is the unifier of motor-intentionality, body-schema, and perceptual / cognitive / affective intentions — the unique vector that binds them
  • is what goes limp in the Schneider case
  • is the 1945 form of what the late ontology will call the "dimensionality" of the flesh — the non-frontal organization of visible and invisible
  • is the structural form of being-in-and-toward-the-world — the arc is how being-au-monde is organized
  • presupposes motivation-mp — the arc connects through motivation, not through causal or logical relations
  • is the 1945 ancestor of intentional-transgression — the late-ontology "transgression" of the other into my phenomenal field is the arc extended to the other
  • is extended by habit — habit reconfigures the arc's reach
  • contrasts with philosophy-of-reflection's "I think" — the arc is not a thinking subject but a situated projection
  • informs the concept of a "field" of presence in Part Three Ch II on temporality

Open Questions

  • MP borrows the term "intentional arc" from Buytendijk & Plessner but never fully explains how his use differs from theirs. Is the arc a continuous concept in the Gestalt-phenomenological tradition, or does MP transform it?
  • Is the arc one vector or several "rays"? MP uses both the singular ("the arc") and distributive language ("projects around us our past, our future...") without quite deciding.
  • The arc is said to project "our ideological situation" and "our moral situation" — but the worked examples in PhP are mostly perceptual-motor. How far do the ideological and moral dimensions of the arc extend? Does the theory of conditioned freedom in Part Three Ch III depend on the arc?
  • How does the intentional arc relate to MP's later renunciation of the tacit-cogito? If the arc is what underlies the "pre-linguistic self-presence," and the tacit cogito is rejected as "still a variant of the pensée de penser," does the arc survive in the late ontology or does it dissolve into the flesh?

Sources

  • merleau-ponty-1945-phenomenology-of-perception — Part One Ch III.j ("The intentional arc"), p. 137. The surrounding sections (III.b–m) are the full analysis of the Schneider case that motivates the introduction of the arc. The term's philosophical weight — beyond the single paragraph that introduces it — is distributed across every subsequent chapter of PhP that invokes the unity of perception, memory, intelligence, and action.
  • heinbokel-2021-johann-to-maurice — Heinbokel uses MP's PhP 137 introduction of the intentional arc and its application to Schneider's symptoms (the "atmosphere of sense" reading) as the methodological-epistemic backbone of his reading. Heinbokel's contribution is the case-report-as-coherent-deformation thesis (see science-as-coherent-deformation and schneider-case); the intentional arc itself is used referentially rather than developed.