They also stated that an act which is not volitional entails the absence of knowledge. Thus, if will is absent from the act, knowledge must be absent. If this necessary consequence—namely, the absence of knowledge—is itself absent, then that which entails it—the absence of will—is also absent, and will is therefore established. Hence, the presence of knowledge in an act entails the presence of will, and its absence entails the absence of will; likewise, the presence of will entails the presence of knowledge, and its absence entails the absence of knowledge.
This is clear, since every volitional act is accompanied by knowledge, while every non-volitional act is unaccompanied by knowledge. Each proposition therefore yields its contrapositive. It may thus be said: whatever is unaccompanied by knowledge is unaccompanied by will, and whatever is accompanied by knowledge is accompanied by will. This establishes that, in an act, the presence of either knowledge or will entails the presence of the other, and the absence of either entails the absence of the other. This is true, and it demonstrates the invalidity of the position of those who affirm knowledge but deny will, namely some philosophers and some Muʿtazilites.
However, none of this demonstrates the invalidity of the approach Ibn Sīnā followed in establishing knowledge. If he argues that He knows what He has created on the grounds that an agent must know his act, and that knowledge of the complete cause entails knowledge of its effect, then this is a sound proof, as explained above—even if he does not mention in the proof that He acts by will. For this is a condition of His being an agent, just as His being alive is a condition of His being an agent, and His possessing knowledge is a condition of His possessing will.
A proof may establish that which is subject to a condition before its condition is known. Afterwards, that condition may or may not become known. Thus, a proof may establish that He acts by choice, while a condition of acting by choice is possessing knowledge. Then, if it is known that He acts