I. The Title: the concept and its figurations
The introduction is titled « You, what have you done with the incommensurable? »
This is an evocative title, and it could almost have been phrased « You, what have you done with your incommensurable? Except that we quickly learn that the incommensurable fissures the unitary subject and its possessivity towards objects, and so the one excludes the other.
The unitary subject is self-commensurable, and self and world co-commensurabilise each other in a vicious circle of reciprocal covering.
The title evokes Paul Verlaine’s famous poem, known by virtually every French schoolchild:
« The sky is, over the roof »
This title is in fact the first line, and the first half of a sentence, which in full reads:
« The sky is, over the roof, So blue, so calme! »
We have here the incommensurable sky soaring above the commensurable roof that covers over the fissures of the real and closes us off from the sky.
The concluding stanza of Verlaine’s poem is even more well-known. It reads:
Oh you, what have you done, you there, Weeping ceaselessly, Say, you, what have you done, you there, With your youth?
The title of the introduction (« »You, what have you done with the incommensurable? ») closely echoes the last two lines of the poem: « you, what have you done…with your youth? »
(Note: both Jullien’s title and Verlaines conclusion echo, no doubt consciously, the Biblical parable of the talents, and the question « what have you done with your talent? » The « talent » being literally a sum of money, and metaphorically the incommensurable gift of life, the gift of the incommensurable.
The substitution of a philosophical concept for a poetic figure or a prophetic image allows us to see both of these latter as figurations of the incommensurable and also to begin to give content to the abstraction as youth and life (Lyotard calls the incommensurable, the « différend », « childhood » in his late writings).
II. The argument: the duplicity of the concept
These preliminary considerations (on Julien’s phases of thought, on the intellectual context of the meta-programme of research of recent French philosophy and on the important role played by the concept of the incommensurable, on Jullien’s creation of the concept of decoincidence, on the poetic and prophetic fgurations of the incommensurable) have prepared us for an attentive, both conceptual and participative, reading of the book as a whole, and of the introduction in particular.
The example of Lyotard prepares us even further. In the quote from Appendice Svelte we see Lyotard give a contextual definition of the « incommensurable » in what we may call its extended sense. He cites deconstruction, disorder, paradox, alterity, nomadism and the encounter as dimensions of this concept. There are many passages in Lyotard that make use of the incommensurable in this extended or general sense.
We know, however, that Lyotard uses the term in a restricted, specific sense to refer to the irreducible heterogeneity between regimes of phrases, such as between the normative and the descriptive regimes. Lyotard moves back and forth between the extended and the restricted sense of incommensurable in his writings, in a sort of pulsation or respiration, just as he moves back and forth between the abstract concept (e.g. the differend) and its concrete figurations (e.g. childhood).
Thus forewarned we can read Jullien’s text with a hermeneutic sensitivity to these shifts and pulsations of meaning, which introduce a duplicity (an incommensurability) into the heart of the concept-image of the « incommensurable ».
The title page of the book is preceded by a first half-title page containing the title « L’incommensurable » in the middle of an otherwise blank page, and followed by a second half-title page containing a question 4/5 of the way down of an otherwise blank page: « Un concept peut-il changer la vie? » (« can a concept change life? »). This question is taken up again in the title of the last chapter of the book.



This disposition in its austerity and in its terms orients us more towards the conceptual pole of meaning for « incommensurable », and reminds us not to take a particular figuration as exhausting the sense of the concept. Figuration is, nevertheless, not wholly excluded here, as the disposition of front matter has the allure of concrete poetry, figuring the orientation of what is to come.
This preliminary orientation shows its usefulness straight away, as we begin with a « crack » or a « fissure » that is presented as potentially the structuring characteristic of « Western » culture, a trait or feature that is both « original » and « originary »:
Could it be a first ideological partisan decision to advance that, in dissociating himself from that which then becomes for him « nature », man has fissured himself inside: original crack, there at the beginning of humanity; as well as originary crack, from which stems the human (page 11, my translation).
This initial figuration of the incommensurable as fissure, crack, dissociation is both dolorist and noetic, binding our consciousness to an original/originary suffering. The duplicity of the origin affects another key term that Jullien introduces here in passing, that of « de-coincidence »:
But that which promoted the human … is that he de-coincided from the heart of the living condition … and that from this dissociation from the rest of life, he remains forever cracked, producing a « himself » that is no longer in direct adequation with the world, nor even, and above all, with « himself » (11)
We may note that in this initial rendering of the incommensurable as « crack », it is negatively connoted and presented as producing and stemming from man’s painful separation from a world that is based on commensurability.
Thus, we may surmise that the argument of the introduction, as foreshadowing that of the book, will be to transmute (without denying) this negativity and to revision the world as itself grounded in, composed of, incommensurables such that our own incommensurability is what unites us with the world rather than separating us from it.
This is indeed the case, as we shall begin to see in the next instalment.