Just as the intellect is one of man’s stages in which he receives an “eye” by which he “sees” various species of intelligibles from which the senses are far removed, the prophetic power is an expression signifying a stage in which man receives an “eye” possessed of a light, and in its light the unknown and other phenomena not normally perceived by the intellect become visible.
112. Doubt about prophecy touches either its possibility, or its actual existence, or its belonging to a specific individual.
113. The proof of its possibility is its existence. And the proof of its existence is the existence in the world of knowledge which could not conceivably be obtained by the intellect alone — such as the knowledge of medicine and of astronomy. For whoever examines such knowledge knows of necessity that it can be obtained only by a divine inspiration and a special help from God Most High, and that there is no empirical way to it. Thus among astronomical phenomena there is a phenomenon which occurs only every thousand years. How, then, could knowledge of that be obtained empirically? The same is true of the properties of medicaments.
114. From this proof it is clearly within the bounds of possibility that a way exists to grasp these things which the intellect does not normally grasp. This is what is meant by prophecy. Not that prophecy signifies such knowledge only.--Al-Ghazali Deliverance from Error. Translated by Richard J. MCCARTHY, S.J.
In the Deliverance from Error (recall here and here), Al-Ghazali presupposes a distinction among three kinds of human faculties: senses (including touch, ordinary sight, etc.), reason, and intuition (or an inner eye). These kinds of faculties are modular and track different kinds of existents. To simplify, the senses treat of or perceive material reality; reason discerns universals; and the inner eye discerns (among other things) certain kind of hidden possibilities and relations (more on this below). Ghazali also assumes a hierarchy among the faculties and the existents they track, but that's not so important in what follows.
In order to show the real possibility even existence of prophecy (recall this piece), Al-Ghazali argues from the success of science (especially astronomy and medicine) which he assumes. (I'll be a bit anachronistic, but if you dislike that you can translate what I say into proper actors' categories.) The key insight that he has is that in science we possess knowledge of events (and relationships among them) that we have not experienced empirically and that are not reached by rational deduction from our grasp of universals. (Universals are hidden essences of things, not laws.) To put it in modern terms, in the context of discovery we're inspired to posit models or theories that go beyond the available evidence in some sense (and thereby guide future research and make predictions that project beyond our empirical evidence). According to Al-Ghazali this inspiration is the product of the inner eye or intuition and that just is prophecy.
Allowing that there are only three such cognitive faculties, we can represent his argument (informally) as follows:
- Successful science predicts events that are unavailable to sensation and rational discernment of universals.
- Science is successful.
- The context of discovery, or model selection, involves an inductive leap beyond what can be known from empirical and rational discernment.
- The success of science is not the product of chance. (Assuming the PSR)
- Thus, the development of successful scientific theory requires guided intuition of structure (or special properties) hidden to the senses and rational discernment;
- Prophecy is guided intuition -->
- Therefore, prophecy is real
That is, Al-Ghazali offers us an inference to the best explanation in the form of an indispensability argument (IBE). (As regular readers know, I am not the world's greatest fan of arguments to IBE.) What's striking about the argument is that even without a commitment to the PSR, we moderns are not in a great position to respond to it (if we wanted to) because to this day, long after the demise of Logical Empiricism, the context of discovery is still shrouded in considerable mystery. There is no widely accepted logic of discovery, and no known method to generate scientific paradigms.* (Model selection theory does not fill the gap.) So, while chance is an option it is not obviously a better explanation than guided inspiration.
So, Al-Ghazali is clear that there is genuine prophecy. But, while Al-Ghazali hints that prophecy and intuition may also involve a kind of special perception and mystical experience, it is notable that his account is also compatible with a rather deflationary interpretation: that prophecy is little more than guided perception of "special properties of things." (122) He is dismissive of miracles like "the changing of the staff into a serpent and the splitting of the moon." (118) And we can know that some such special properties have been intuited (by the inner eye) by a prophet in virtue of the events or things inferred from theoretical or practical or political knowledge. (So you can also be a prophet of special moral or political qualities. ) That is to say, prophecy results in moral, political, and theoretical knowledge and we judge this by its fruits. (Religious) Prophets are physicians of the maladies of the heart, and we can experience their skill if the hearts they treat are healthy. (Prophets play a political and social role in guiding the laws and mores/norms of the community.) But in this work, Al-Ghazali leaves it unclear how we should understand the nature of inspiration or God's guidance (he does so elsewhere). As he writes (96),
There was what was of what I do not mention:
So think well of it, and ask for no account!
*I have a very good PhD student, Laura Georgescu, working on developing an account of how pre-paradigmatic science is turned into paradigmatic science, and my teacher, George Smith and his friend Bill Harper have written on how to to turn rough data into high quality of evidence in pre-paradigmatic states.