Library · A reader’s index · sixteen sources · one idea

Thirdness

What a dozen thinkers, across twenty-four centuries, have said about the one who is neither of the two — and why the third turns out to be the condition for meaning, groups, justice, and anything new.

tertium· the third thingLatin tertius, “third”; tertiumis its neuter — not the third person but the third something. It survives in two idioms that pull against each other: tertium quid, “a third something” that belongs to neither side, and tertium non datur, “a third is not given” — logic’s rule that there is no middle between true and false.One tradition names the third to include it; the other names it to exclude it. This index is about the argument between them.

The gist, in six moves

PeirceTwo things side by side don’t mean anything. Meaning, law, and habit are what a third does.
SimmelTwo people are not yet a group; either can end it alone. The third makes something that outlives its members.
LevinasFace to face, obligation is bottomless. The third party is what forces comparison — and so justice, law, institutions.
Winnicott · Buber · JungThe new is not made by either party. It is made in the between, when the between is held.
BenjaminThe third is not a person. It is a function, a position — something two people can hold together.
Simmel · Serres · GirardThe same seat holds the profiteer, the divider, the parasite, and the scapegoat. Thirdness is a power, not a virtue.

Each card below carries the source’s own sentence, verbatim, with a plain reading under it. The filters ask one question of every source: what does the third do here?

The third…

16 of 16 sources

primary text in handreliable secondary quotationwording still to verify

c. 385 BCEPhilosophy

Plato, SymposiumDiotima's teaching on the daimonic

“The whole of the daimonic is between god and mortal” — interpreting and conveying in both directions, “so that the whole is bound together with itself.”

Plato, Symposium202d–203a (Diotima; attribute to the character, not to Plato flatly). Rendering to be pinned to one translation before print.

Plain reading. Eros is not a god but a daimon— a go-between. The gap between mortal and divine is not empty; it is populated, and what lives there carries messages both ways. The oldest Western picture of a third is a ferryman, not a judge.

The third here is a messenger who binds two worlds into one whole.

metaxydaimonthe between

c. 1875Logic · Semiotics

C. S. Peirce, “Third”a fragment

“By the third, I mean the medium or connecting bond between the absolute first and last. The beginning is first, the end second, the middle third. The end is second, the means third. The thread of life is a third; the fate that snips it, its second. A fork in a road is a third, it supposes three ways; a straight road, considered merely as a connection between two places is second, but so far as it implies passing through intermediate places it is third.”

Collected Papers1.337 (fragment “Third,” c. 1875).

Plain reading. Anything that is a means, a middle, a passing-through, is a third. A road is second if you only care that it joins two towns; it is third the moment you notice it goes through somewhere. The category is about mediation, not headcount.

The third here is the medium — the bond between a first and a last.

mediationcategories

c. 1887–88Logic · Semiotics

C. S. Peirce, A Guess at the Riddlethe three categories, defined

“The first is that which is what it is without reference to anything else… The second is that which is what it is by force of something to which it is second. The third is that which is what it is owing to things between which it mediates and which it brings into relation to each other.”

Collected Papers1.356; and 1.362: “there is no absolute third, for the third is of its own nature relative.”

Plain reading.Firstness is a quality on its own; Secondness is brute reaction, one thing against another; Thirdness is whatever holds two things in relation — a sign, a law, a habit, a meaning. You cannot build relation out of the two things related. And there is no third “in itself”: a third is always a third of something.

The third here is relation itself — and it can never stand alone.

signlawhabit

1908Sociology

Georg Simmel, Soziologiewhy two is not yet a group

“The social form rests directly on the one and on the other. The departure of either would destroy the whole, so that it never reaches that supra-personal life which the individual feels as independent of himself; whereas already in an association of three, a group can go on existing when one member leaves.”

Soziologie (Leipzig, 1908), ch. 2, pp. 81–82. English in Wolff, ed., The Sociology of Georg Simmel(1950), “The Dyad” / “The Triad.”

Plain reading. A pair has no life above its two members: each of them can end it alone, and each knows it. Add a third and something appears that none of them is— a group that survives any one of them. The third is what makes a “we” that is not just “you and I.”

The third here is what gives a relationship a life of its own.

dyadtriad

1908Sociology

Simmel, “The impartial one and the mediator”the first of three forms the third takes

“The third is impartial either when he stands beyond the contrasting interests and opinions, untouched by them, or when he shares equally in both.”

Soziologie(1908), ch. 2 §1 “Der Unparteiische und der Vermittler,” p. 107; the section opens p. 103.

Plain reading. There are two ways to be neutral: be outside both parties, or be equally inside both. Simmel then splits the neutral third into the mediator, who tries to “switch himself off” so the two can connect directly, and the arbiter, who takes the rival claims into himself and settles them. Same neutrality; opposite amounts of power.

The third here is the one who holds the group together by belonging to neither side.

mediatorarbiterimpartiality

1908Sociology · the shadow

Simmel, “Tertius gaudens”the third who enjoys

“The impartial one can evidently also exploit his relatively superior position in a purely egoistic interest: where before he behaved as a means to the group’s ends, here he inverts it, making the interplay between the parties, and between himself and the parties, a means to his own.”

Soziologie(1908), ch. 2 §2 “Der Tertius gaudens,” p. 111.

Plain reading. Nothing about the seat between two parties makes the one sitting in it good. The mediator and the profiteer occupy the same position; the difference is only what each does with it. The tertius gaudens — “the third who rejoices” — is the mediator with the sign flipped.

The third here is the one who lives off the quarrel.

profitsame seat

1908Sociology · the shadow

Simmel, “Divide et impera”the third who makes the quarrel

“…that the third deliberately founds the quarrel in order to gain a dominating position.”

Soziologie(1908), ch. 2 §3 “Divide et impera,” p. 119.

Plain reading.One step further than profiting from a conflict: manufacturing it. Two parties who were united, or dependent on each other, are split so that each now needs the third. Simmel treats it as a “nuance” of the previous form that is not always separable from it in real life — which is exactly the problem.

The third here is the one who creates the gap it then occupies.

manufacturerule

1916 / 1958Depth psychology

C. G. Jung, “The Transcendent Function”the living third

Holding two opposed positions together “generates a tension charged with energy and creates a living, third thing — not a logical stillbirth in accordance with the principle tertium non daturbut a movement out of the suspension between opposites, a living birth that leads to a new level of being.”

Collected Works8, “The Transcendent Function” (written 1916, published 1957/58), §189 region. Wording to be checked against a clean 2nd-edition CW 8 before quoting.

Plain reading.Jung takes logic’s rule that “a third is not given” and says: in the psyche, it is. If you can bear two irreconcilable positions at once without collapsing into either, something appears that neither side contained — not a compromise but a new position. The cost is the bearing.

The third here is what is born when opposites are held and not resolved.

oppositestertium non datur

1938 / 1947Philosophy of dialogue

Martin Buber, Between Man and Manthe between is real

“On the far side of the subjective, on this side of the objective, on the narrow ridge, where I and Thou meet, there is the realm of ‘between.’”

Between Man and Man(tr. R. G. Smith, 1947), “What Is Man?” (1938 lectures). Widely quoted; page to pin.

Plain reading.Buber’s claim is ontological, not sentimental: the between is not “in” either person and not a thing in the world. It is a third region with its own reality, and it is where the encounter actually happens. What you cannot locate in me or in you may still be the most real thing in the room.

The third here is a place — the narrow ridge neither of us stands on alone.

das ZwischenI–Thou

1953Psychoanalysis

D. W. Winnicott, “Transitional Objects and Transitional Phenomena”the third part of a life

“…the third part of the life of a human being, a part that we cannot ignore, is an intermediate area of experiencing, to which inner reality and external life both contribute.”

International Journal of Psycho-Analysis34 (1953): 89–97, §I.A.1. Also §I.D: “an intermediate area of experience which is not challenged (arts, religion, imaginative living, creative scientific work, etc.).”

Plain reading.There is inside, there is outside, and there is a third area that is neither — where the infant’s blanket is both found and made, and where, for the rest of life, play, art, and religion happen. Winnicott’s point is that this area is not a stage to grow out of. Culture lives there.

The third here is the space where things are neither invented nor found, but both.

transitionalplayculture

1961 / 1972Anthropology · the shadow

René Girardthe mediator of desire; the scapegoat

“The mediator is there, above that line, radiating toward both the subject and the object. The spatial metaphor which expresses this triple relationship is obviously the triangle.” — and, a decade later: “When unappeased, violence seeks and always finds a surrogate victim. The creature that excited its fury is abruptly replaced by another, chosen only because it is vulnerable and close at hand.”

Deceit, Desire, and the Novel (1961; tr. Freccero, 1965), p. 2; Violence and the Sacred(1972; tr. Gregory, 1977), p. 2. Girard’s total theory is contested — take the mechanism, not the cosmology.

Plain reading. Two darker thirds. First, the third is the sourceof wanting, not a bystander to it. Second, a community in crisis makes itself whole by throwing someone out — and the marginal, the liminal, the one who doesn’t fit either side, is who gets chosen. The same mark that qualifies someone as a go-between qualifies them as a victim.

The third here is the one the two expel in order to become one.

mimesisscapegoatexpulsion

1974Ethics

Emmanuel Levinas, Otherwise than Beingle tiers — the third party

“The third party introduces a contradiction in the saying whose signification before the other until then went in one direction. It is of itself the limit of responsibility and the birth of the question: What do I have to do with justice?”

Otherwise than Being, or Beyond Essence(1974), tr. Lingis (1981), p. 157 — as quoted in the Stanford Encyclopedia of Philosophy, “Emmanuel Levinas.” Check against Lingis in hand.

Plain reading. For Levinas, facing one other person puts you under an obligation with no limit. What limits it is not selfishness but the arrival of a third— the other’s other, who also has a claim. Now you must compare, weigh, measure. That act of measuring is the origin of justice, of law, and of every institution. Institutions exist because there is always a third.

The third here is the one whose presence turns care into fairness.

justiceinstitutionsthe other's other

1980Philosophy · the shadow

Michel Serres, The Parasitethe excluded third

“As soon as we are two, we are already three or four. We learned that a long time ago. In order to succeed, the dialogue needs an excluded third; our logic requires the same thing.”

The Parasite(1980; tr. L. R. Schehr, Johns Hopkins, 1982), p. 57. Also p. 7: “To parasite means to eat next to”; and p. 79: “Relation is nonrelation. And that is what the parasite is… There are channels, and thus there must be noise.”

Plain reading. French parasitemeans three things at once — static on a line, a freeloader at a table, an organism on a host — and Serres says they are one thing. Every relation has a third in it: the noise the message must exclude, the guest the meal must feed, the one whose exclusion lets the two succeed. The third is also interference — and interference is where anything new gets into a system.

The third here is the noise a relation must exclude, and cannot quite.

noisethe excluded

1994Psychoanalysis

Thomas Ogden, “The Analytic Third”a third subject in the room

The analytic relationship produces a third subject — the “analytic third” — jointly created by analyst and patient, which neither owns, and from which both can work.

International Journal of Psycho-Analysis75 (1994): 3–19. Paraphrase.

Plain reading.Two people in a consulting room generate something between them that is not either of them — with its own moods and thoughts — and the work is done from there. The third is not the therapist. It is what the two of them, together, cannot help making.

The third here is a subject the two create and neither controls.

intersubjectiveco-created

2000Conflict resolution

William Ury, The Third Sidethe community around a conflict

The third side is “people—from the community—using a certain kind of power—the power of peers—from a certain perspective—of common ground—supporting a certain process—of dialogue and nonviolence—and aiming for a certain product—a ‘triple win.’” Its ten roles: provider, teacher, bridge-builder, mediator, arbiter, equalizer, healer, witness, referee, peacekeeper.

The Third Side: Why We Fight and How We Can Stop(Penguin, 2000), the “five P’s” definition and ten roles as given on the author’s own site (thirdside.williamury.com) and in the Beyond Intractability summary; book page to pin.

Plain reading.Ury pluralises the third. It is not one wise person between two parties but the whole ring of people around them, each of whom can do something — and the list runs from the mildest (witness) to the most forceful (peacekeeper). A “triple win” is a settlement that meets both parties’ legitimate needs andthe community’s. The third side is the community acting as a third.

The third here is everyone who is not one of the two.

ten rolescommunity

2004Psychoanalysis

Jessica Benjamin, “Beyond Doer and Done To”the third as a function, not a thing

“I consider it crucial not to reify the third, but to consider it primarily as a principle, function, or relationship, rather than as a ‘thing’… we are not holding onto a third; we are, in Ghent’s felicitous usage, surrendering to it.”

Psychoanalytic Quarterly73 (2004): 5–46. Also: “thirdness as a quality or experience of intersubjective relatedness that has as its correlate a certain kind of internal mental space.”

Plain reading.When two people lock into “doer and done to” — each feeling the other is the one acting — there is no third, only twoness. The way out is not a referee. It is a position both can stand in together, which neither holds and both surrender to. The third is something you enter, not someone you call.

The third here is a position two people can occupy at once.

complementaritysurrenderrecognition

The same seat, five ways to sit in it

The strongest thing this index shows is that the sources disagree about the third’s character while agreeing about its position. Collected here so that the idea is not a hymn.

The third as	Source	What it teaches
mediator	Simmel §1; Ury	The position can hold a group together — by belonging to neither side, or equally to both.
tertius gaudens	Simmel §2	The position can be monetised. Nothing in the seat prevents it.
divide et impera	Simmel §3	The position can manufacture the conflict it then mediates.
parasite	Serres	The third is also interference — the noise a relation must exclude to work, and the route by which anything new gets in.
scapegoat	Girard	The third can be the one expelled so the two become whole; the mark of the go-between is the mark of the victim.

Where they pull against each other

Three arguments the sources are having with one another. These are the places to think, not the places to resolve.

Simmel vs. Levinas

For Simmel the third is an opportunity— a position from which one can reconcile, profit, or rule. For Levinas the third is an obligation— its arrival is what forces me to be just. One sees the seat from inside it; the other sees it from the face of the person it interrupts.

Logic vs. Jung

Tertium non datur: between true and false there is no third. Jung’s reply is that in the psyche there is, and it is alive. Peirce sits between them — a third is real, but “of its own nature relative,” never a thing on its own.

The referee vs. the position

Ury’s ten roles are all peopledoing things. Benjamin and Ogden insist the third is not a person at all but a function or a co-created subject. Simmel quietly agrees: the mediator’s art is “to switch himself off.” The most useful third may be the one nobody is.

Where to read next

In roughly the order a newcomer would find most rewarding.

Simmel, “The Dyad” and “The Triad”— in Wolff, ed., The Sociology of Georg Simmel (Free Press, 1950). Forty pages; the whole social form of the idea.
Benjamin, “Beyond Doer and Done To” — Psychoanalytic Quarterly 73 (2004). The clearest modern statement that the third is a position.
Winnicott, “Transitional Objects and Transitional Phenomena” — IJP34 (1953). Nine pages; where “the third part of the life of a human being” is named.
Peirce, “A Guess at the Riddle” — Essential Peirce vol. 1 (Indiana, 1992), or CP 1.354–1.416. Read for the categories only.
Levinas, Otherwise than Being, ch. V §3 “From the Saying to the Said” — difficult; read the third-party pages (Lingis, 157–162) with the SEP entry open.
Ury, The Third Side(2000) — the practitioner’s version; skim for the ten roles.
Serres, The Parasite(1980/1982) — the antidote to idealising any of the above.
Girard, The Scapegoat(1982) — the shortest route into the expulsion mechanism.