  In Arbiter (Arbitrator or Umpire), written about the same time as the Council of Constantinople and surviving only in Syriac translation, Philoponus takes the view that the locution ‘discernible in two natures’ ought to be abandoned. His main strategy is to argue that in this context the meaning of the terms ‘nature’ and ‘hypóstasis’ are essentially identical, so that if Christ is (according to (3)) one hypóstasis he cannot also (as in (4)) be discernible in two natures. The argument goes roughly as follows: The term ‘nature’ has two applications, one general and one particular: we can speak of the nature of man in general or of the particular nature of this individual man. Now, when one speaks of the unification (and discernibility) of two natures in Christ, this cannot be meant to say that the universal natures of godhead and manhood have been unified in Christ (else it would be also true to say that not only the Logos, but also the Father and the Spirit have become man, since the universal nature of godhead applies to them as much as it does to the Logos). Instead, the reference must be to the particular nature of the divine Logos and the particular nature of Jesus the man: it must be with reference to these particular natures that godhead and manhood are combined in Christ. But this too cannot be right, Philoponus claims, since ‘particular nature’ means the same as ‘hypóstasis’, which he uses as a synonym also of ‘person’ and ‘individual being’. Since it is agreed that Christ is one person and one hypóstasis, he must consequently also be of one ‘particular’ nature only, not two. Philoponus concedes, of course, that the nature of Christ is not an ordinary one; it is complex, combining and preserving the properties of both what it is to be a god and what it is to be a man. Far from being able to discern two different natures in Christ, we should speak of one complex or combined nature (mía phúsis súnthetos).