 Maritain writes that there can be knowledge of the divine attributes. As with all natural knowledge of the divine, this knowledge is basically analogical, and it is often the result of a via negativa. Thus, he insists that we know some things about God. We can know that God is (quia est), though not what God is in himself (quid est) (Degrees of Knowledge, Appendix III, 1932 [1959: 423]). Moreover, against A.G. Sertillanges and Etienne Gilson, Maritain maintains that we can have affirmative knowledge about God—i.e., know in a more or less imperfect but, nevertheless, true way what God is. Besides, Maritain holds, knowledge through negation presupposes positive knowledge. (Mary Daly notes, however, that Maritain is not clear about the extent to which our affirmative knowledge of God is arrived at by means of philosophical argument [Daly 1966: 53.].) Nevertheless, Maritain acknowledges that the knowledge of God that philosophy provides is incomplete and imperfect; the analogical knowledge that we have of God falls short of a complete description of what God is.