Kant’s Copernican Revolution

Intelligible world is the span of rationality, that is, all that can be derived by reason generate the intelligible world. And sensibility is the capacity to be passively affected by objects. So by sensible world we mean all the sensuous experience we have. Now it is to see that reason itself moves by its own laws independent of how an individual comprehends them. Only in this sense, intelligible world must be independent of human understanding. It is also independent of sensible world as sensual datum should not affect the integrity of reason. But then how can we have any understanding of the intelligible world if it does not affect us? That is how a can we have a priori knowledge of reason? We can not. Intelligible world can be grasped only through sensible world, through its passive effect on us.

Human understanding is not a passive action of receiving sensuous data only, it is the active process of synthesizing these data. In this activity lies the intelligibility of the “world”.

Here we have to look at Kant’s Copernican revolution. Copernicus spoke in favour of a heliocentric universe (solar system) instead of a geocentric one – removing humans as the centre of god’s creation. The observer is not in the centre of the observable world (although spatially we ARE at the centre of our observable sphere) looking at celestial bodies in motion, rather the observer is also moving along with these bodies. Kant said that not only we passively sense the sensible world, we actively synthesize the sensed data using our mental faculties to construct our understanding. But here Kant mentions – it will be wrong to find the knowledge of intelligible world in the content of our understanding of the sensible world. Rather we have to look into the process of synthesis, so as to follow up the laws that are in our mental faculties which govern the process of understanding (synthesis).

So it can be said that intelligibility lies in the form of understanding as fundamental laws governing it. These laws can be identified by reflecting on the possibilities of experiences. Since if I begin with a handful of experiences (where sensuous data has been synthesized in understanding) and reflect upon all other possible experiences – we will basically follow up the same laws of understanding along all of them. But this implies the sensible world (formed by our passive experience and well-defined in our understanding) must conform to these laws. Even if we experience a baffling event that challenge our preconceptions, we can introspect more deeply and make inferences without contradicting the laws of understanding. It can even be an inference about these laws, but then our knowledge of these laws change, not them so to say. But these implies human understanding can not go beyond the possibility of experiences or know about anything independent of our mind i.e. the existence of noumenon is not that can be refuted.

But what I think is that the true Copernican project does not stop here. Let us look at relativity. It is not only that the observer is in motion like the observant, their relative motion alters the observation to great extent. Or look at Quantum Mechanics, where the process of observation itself alters the state of observant. So the Hegelian turn I would take is as follows:

It is not that we passively sense the objects and actively synthesize that sensuous input. The process of sensation itself is an active process where the object can be affected as well. So although we can not know of noumena, we compel it by the process of phenomena to conform to our understanding. Even if we can not determine the nature of the thing-in-itself we can however determine negatively its motion. The object and the subject are both in becoming determining each other on the horizon possibility/impossibility of understanding.