One of the deeper questions that runs throughout philosophical speculation — Western, Eastern, and besides — is a kind of wonder or awe at the fact that the world does make any sense to us all. This awe can be expressed as itself an intellectual problem: why is the world intelligible? The question is sometimes put as: what is the source of the world’s intelligibility? Is the source of intelligibility itself intelligible? Or does a mystery remain after all explanations have had their say?
I was reflecting on the very idea of intelligibility after a long day of teaching Aristotle’s politics in one class and Kant’s ethics in another. For Aristotle, there are genuine facts about the world, and especially about human nature, to which any adequate normative theory must be responsive. For Kant, the situation is reversed: any genuinely normative theory must be based wholly a priori, since no empirical theory can be guaranteed to be universally and necessarily true.
For realists like Aristotle, the intelligibility of the world is what we discover to be case, and our thoughts are true if they match up with how the world really is. We aspire to carve the world at its joints, so to speak. For idealists like Kant, the intelligibility of the world is only the intelligibility of our experience of the world, and therefore depends on how the mind actively organizes the barrage of sensations it receives.
The dilemma for realists has always been that people from different cultures and time-periods propose quite different and even incompatible ontologies, so how can anyone justifiably say that the ontology of their time and place is the one that correctly carves the world at its joints?
The dilemma for idealists is more complicated, but a good deal turns on the fact that it just pushes the bump in the carpet around. Being told that the source of the world’s intelligibility lies in us is all well and good, but how to explain the fact that the world’s intelligibility lies in us? Where did our ability to interpret the world so as to make sense of it come from?