Now, it was not a fact that he was able to explain the heaven of Christianity and the world as we see it, I cannot say he reconciled the two. I only wanted to speak about it because there was the kind of a reflection of Christian thought on him and he had a insight which he had got from Christian theology that this world by itself cannot be explained, unless you accept rationally the existence of God, therefore he believed in God to be rational and God rational in the sense that he who harmonises and allows events to occur because they are harmonious with each other. And therefore rationality of man consists in discovering the harmony. Now this insistence upon harmony and perception of harmony as a part of rationality was approved by Leibniz very powerfully. You will recall, I am speaking in parenthesis, Sri Aurobindo says in the very first chapter, ‘All problems of existence are essentially problems of harmony.’ It is one of the most fundamental rational propositions that Sri Aurobindo has made in The Life Divine. ‘All problems of existence are essentially problems of harmony.’ Rationality is guided by seeking for harmony, where there is no seeking for harmony, it’s not rational. If you don’t seek harmony anything can happen it is pell–mell, the world is pell–mell. It is not rational.
Now we have reached only the mid–point of the development of rationality as it developed in the West. We move forward and we find that thereafter there was a turn in the Western thought, a new development of thinking as to what is irrational and what is rational? And there developed the theory of empiricism, as opposed to rationality. In other words the entire tradition of Plato came to be questioned. Now this questioning was inherent actually in Aristotle, as we marked earlier that Aristotle tried to combine the becoming and being and he revolted against Plato because Plato was not able reconcile being and becoming and he thought that he could do so, and if you look at it impartially it did not actually succeed in doing it. But the …..there was as it were kind of a trend of thought, the trend emphasised the being and universality and permanence on the one hand and the movement which emphasised becoming. And although up till now there was some wave of combining being and becoming, although in a very loose manner, in a haphazard manner and the problem had remained unresolved. There was here now a clear departure which said that Plato and all his tradition was fundamentally not rational. It does not take into account sufficiently the world as we see it, the becoming is very much minimised, the importance of the becoming is very much minimised in the whole history of philosophy, accept Aristotle tried to give some place to it and Leibniz, who gave place to it through his theory of compossibility. But neither Leibniz was able to reconcile being and becoming, nor was Aristotle was capable of doing it. Therefore instead of clearing the barriers of the problem all the time, a time came when they said: we should not be blocked by these barriers of universality, behaviour of permanence and this Law of Necessity and a new trend arose in which they said we should see the becoming as it is, not in the context of permanence and universal but we should see the world of becoming as it is and how do we know the world of becoming? By experience. It is not by the help of the idea of universals, permanence and all that of which Plato and others had spoken. We will see the world as it is by experience.
Now this emphasis on knowledge of, by experience, an ideation or rationality which follows the logic of the becoming became now a more prominent feature and that movement is right up till now continuing. Empiricism ultimately came to a climax in Hume. And Hume pointed out that experience is the only means of knowledge and we have no experience in the world except sense experience. In the sense experience that is no perception of universality, no perception of permanence, no perception of causality, no perception of explanation, the whole world is simply what it is and take account of the world as it is and rationality consists in doubting any proposition which speaks of certainty of knowledge, which speaks of universality of knowledge, absoluteness of knowledge, confine yourself only what you can know probably. And therefore he is regarded as a sceptic. So scepticism became the hallmark of rationality. Becoming had to be understood directly and his becoming can be understood with no other standard excepting doubting. You can make even the Laws of Induction, where according to him not sustaining, even the laws of science, he said even scientific knowledge can be questioned. So rationality came to consist in physicality and scepticism. So this is another mark of rationality, which came to be underlined in the Western thought.
It seemed as if with the arrival of Hume, rationality came to conclude that nothing can be known, and to assert nothing can be known is a rational proposition and no other rational proposition as drawn. This created a great crisis in the Western history of rationality. Is it really true that scientific laws which seem to give necessities, are they not valid? Is it not a fact that things can fall and must fall direct, how do you know? But if experience is the means of knowledge and the only means of knowledge, you can only say: I see things falling, do you see they must fall? In experience you don’t see they must fall. They are falling, but there is nothing that they must, necessity is never seen. That the sun will rise tomorrow is expectation and maybe it does rise tomorrow but there is no necessity it must rise tomorrow. Hume says: I come out of my room and go away and my room is on a hill, and nobody perceives it at all, how am I to be sure that this room does not disappear when I go out of the room? It is true that when I come back it is there, it is quite possible that it is always there when I see it but there is no necessity that the house must be continuing to exist. Now many of the propositions, many of the people laugh at but actually they are very serious propositions and it is because of the seriousness that Kant said he himself was awakened from his dogmatic slumber by Hume. By reading Hume, he felt he himself was carrying a dogmatic slumber and Hume carried him so powerfully that he was awakened and because he was awakened he felt the necessity of reformulating the whole rational fabric of human mind, tried to understand it and that’s why he wrote the famous book called The Critique of Pure Reason, that is the whole theory of reason as he defined, it is actually important. He said that our human rationality consists of four complexions, you might say four boxes, you might say, four spectacles and two additional spectacles, four he called four categories and two he called two intuitions. They are automatic in your human mind. Rationality consists of putting everything in space and time. It is inevitable that whatever you think the becoming, you cannot but see it in the context of space and time, of this you can be absolutely sure, why because the structure of reason is such, human mind is such and you cannot transcend human structure it is there, your structure of the brain, nobody can think it, it is there planted upon you. So you must see space and time, everything is in space and time and there are four categories, everything in the world can be summarised into four forms, – quantity, quality, relation, modality. There is nothing in human knowledge which can transcend these four forms. Why and many and plenty, there is no other quality positive, negative and neutral, relation, causality etc. etc. but they may be, mat not be and will not be. These are the only modes of pure existence. There is no other proposition excepting twelve propositions that you can make and all in space and time, so twelve forms of proposition, under four categories, each one with three propositions. So rationality consists in finding every proposition in this form. When one of the forms of proposition if it is fitted in, is rational provided it is put in the context of space and time but this is all what he calls phenomena and this is what he calls phenomenal reality. But he saw that phenomena themselves, this is the important point, rationally take you to that which is beyond phenomena. He perceived that if you are rational, you have got to affirm that phenomena by themselves are only structures. There must be a reality behind it, behind the phenomena, which he called noumenal, phenomenal is what we see around and there is a noumenal. Therefore rationality consists in analysing all the phenomena under twelve propositions provided they are in the form of space and time. But leaving this proposition at the same time that all these ultimately must be grounded in what he called the transcendental. He said that transcendental is not merely a possibility, it’s a necessity of thought; to be rational is to be absolutely certain there must be a transcendental. In a sense you might say he was reaffirming Plato and the whole rationalistic movement. But again he said what is that noumenal? As long as we have got this reason, we can never know because you cannot transcend the structure. Whatever we see, whatever we know, will only be in this form, therefore we can only be sure that there must be a ground, there must be a transcendental, the transcendental cannot be known. Therefore his philosophy is called agnosticism, not scepticism because he is sure there is a ground but it cannot be known therefore it is agonistic, you cannot know, you are sure it cannot be known. So rationality consisted in admission of agnosticism regarding the transcendental and framing everything that we see in the world under these twelve propositions. But he added one important thing and that brings now the concern for moral ideas.