Philosophy and scriptural interpretation › Learning from people outside one's religion

The next part of the argument concerns intellectual inheritance. A single person cannot begin every science again. Averroes points to the cumulative character of fields such as geometry and astronomy. Philosophical investigation likewise requires making use of predecessors rather than treating all earlier work as though it had never happened.

That requirement includes predecessors who did not share the inquirer's religion. In section 6, Averroes compares a valid intellectual instrument to a tool used in a valid sacrifice. The relevant question is whether the instrument meets its conditions, rather than the religious identity of its owner. The analogy supports using a sound method without first demanding religious agreement from its discoverer.

His acceptance is conditional. In sections 7 and 9, he calls for accepting what is true and identifying what is mistaken in earlier writings. Studying the ancients is therefore not the same as accepting every ancient conclusion. The distinction protects the inquiry from replacing religious conformity with uncritical philosophical conformity.

There are consequently two errors to avoid within his account. Rejecting a sound argument because of its origin obstructs inquiry. Accepting an unsound argument because of its origin obstructs it too. The required assessment concerns the argument itself, including the premises that its earlier readers may have taken for granted.

Consider a hypothetical reader who distrusts a proof because its author belonged to another religious community. Averroes's argument asks the reader to examine whether the proof works. Conversely, the author's prestige does not turn an error into knowledge. This illustration states the implication of his argument; it is not an episode reported in the treatise.

He then distinguishes essential benefit from incidental harm. Some people become confused through study because of poor preparation, disordered reasoning, passions, or lack of a teacher. That does not, he argues, justify preventing a suitable student from studying. His comparison is with denying water to the thirsty because someone has choked while drinking it.

The comparison does not establish that every philosophical course is beneficial. It identifies what a prohibition would have to show. An example of harm is insufficient if the harm depends on conditions that appropriate education can address. A reader can ask whether the proposed distinction actually fits the kinds of philosophical disagreement at issue.