Of his predecessors among the Jewish philosophers Ibn Ezra shows closest relation to Solomon ibn Gabirol. He does not quote the "Fountain of Life," but he names its author as a great thinker and writer of poems, and shows familiarity with Gabirol's doctrines. Like Gabirol he says that all except God consists of substance (matter) and form. Not only the sublunar things, subject to generation and decay, but the higher incorporeal things, also, are in essence two, _i. e._, are composed of two elements, subject and predicate. God alone is One; he is subject only and not predicate. And Ibn Ezra also has some allusion to the divine Will as taught by Gabirol.
In giving a connected sketch of Ibn Ezra's philosophical ideas, the most one can do is to collect all the sayings bearing upon our subject which are found scattered through Ibn Ezra's writings, and classify them and combine them into a connected whole. This has been done before by Nahman Krochmal[215] and by David Rosin,[216] and we shall follow the latter in our exposition here.
God is the One. He gives forms to all things, and is himself all things. God alone is the real existent, all else is an existent by virtue of him. Unity is the symbol of God because in number also the unit is the foundation of all number, and yet is not itself number. It exists by virtue of itself and needs not the numbers that come after. At the same time the unit is also all number, because all number is made up of the unit. God alone is one, because he alone is not composed of matter and form, as everything else is. God has neither likeness nor form, for he is the creator of all things, _i. e._, of all likeness and form. He is therefore incorporeal. In God the subject knowing and the object of his knowledge are one and the same thing. Else he would not be one. In knowing himself, therefore, he knows the universe. God as the cause and creator of all things must know all things, the universal as well as the particular, the world soul as well as the various species, and even every single creature, but he knows the particular in a general way. For God knows only what is permanent, whereas the particular is constantly changing, hence he does not know the particular as such, but only as involved in the general and permanent.