Immanuel Kant

In the Middle Ages, theology was the queen of the sciences, and philosophy was regarded as her handmaiden, and there was a certain intellectual credibility to the truth claims of Christianity.

But since the Kantian critique of the traditional arguments for the existence of God, for example, philosophy has been liberated from theology, and the impact of theology and the church has declined dramatically in the last 200 years. Each Saturday, we have been reminded that how we think matters, that ideas have consequences. Therefore, a study of philosophical thought helps us trace how the Western world and society came to embrace the ideas of the present day. And today on Renewing Your Mind, R.C. Sproul will introduce us to one of the most influential and controversial Enlightenment thinkers, Immanuel Kant. R.C. Sproul sought to help Christians know what they believe and why they believe it, and a study in philosophy shines a light on ways our own thinking may have been influenced by the world rather than the Word. You can own Dr. Sproul's entire overview of philosophy on a special edition DVD along with a digital study guide when you give a gift of any amount at renewingyourmind.org. So who was Immanuel Kant, and why has his influence been so significant? Here's R.C.

Sproul. When historians and cultural analysts look at our contemporary civilization, they frequently use words to describe the situation that are prefaced by the word post. We hear this generation called the postmodern era, or the post-Christian era, or perhaps even more frequently, the post-Kantian era. The reason for that description is that all theoretical thought since Immanuel Kant has to be understood in light of the groundwork that he achieved in the eighteenth century. And I think there's a link between post-Kantianism and what we call the post-Christian era, because Immanuel Kant, more than any other individual, gave the most devastating critique of classical theism that's ever been launched. And that created a crisis in apologetics, in the rational defense of historic Christianity, and the like.

Now, I've mentioned in the past, all the way back at the beginning of our series, of a tendency for cycles to take place in the history of theoretical thought, when tension occurs between two dominant schools of thought, that immediately after that comes a period of skepticism, and that period of skepticism tends to prevail until somebody comes along and produces a new synthesis that will reconstruct the ground basis for theoretical thought. We saw that in the tension that arose between the thinking of Parmenides and Heraclitus, which was then resolved by Plato, and then we saw another tension between Plato and Aristotle, which really didn't get resolved until the Christian synthesis of Augustine, and so on. Well, now, in the 17th and 18th century, we saw this terrific tension between the schools of rationalism and empiricism, ending in the radical skepticism of David Hume.

And what follows out of this in the 18th century are two really different movements, although they're closely related. One was the origination of the so-called Enlightenment, which we'll treat at another time, but mainly we're concerned today with the impact of Immanuel Kant. Now, to simplify things, we can say that the whole history of philosophy prior to Kant can be divided between two general schools of thought, rationalism on the one hand and empiricism on the other. So, again, I'm painting with a broad brush here and working a little bit loosely at this point, but if we were to go through history and look at these strands of thought under rationalism, we might put Parmenides, and Plato, and Plotinus, and Augustine, and so on, dropping down then to Descartes, and Leibniz, and Spinoza, and Paschal.

On the empiricism side, we would include such people as Heraclitus, and then Aristotle, and then Aquinas, and Bacon, and then into Locke, and so on, so that we could, as I said, if we're loose enough, put every major thinker, and some would go into the rational side, into one or the other of these two camps. Now, perhaps the most important philosophical synthesis ever achieved was that achieved by Kant when he took both of these schools, borrowed from each, he criticized certain aspects of each side, borrowed the good things from each side, and produced a whole new approach to knowledge. Now, we'll go over that in a few moments, but after Kant achieved his synthesis, you might think, well, then that would be the end of the history of Western philosophy. But, in fact, what happened is out of Kant's watershed work came, either directly or indirectly, all the modern schools of philosophy that compete with one another for acceptance since Kant. From Kant, we can trace the roots, for example, of idealism, of Marxism, of logical positivism and analytical philosophy, or existentialism, or phenomenology, or pragmatism, or relativism, or pluralism. That is to say virtually all of the movements of the 19th and 20th century that have emerged since Kant trace their origins in their roots to some aspect, some dimension of the work that he initiated.

Now, let's take a few moments to look at the basics of his synthesis. If you recall, we saw that the differences between the rationalists and the empiricists included the rationalists believed in the priority of the a priori, that is, of innate ideas, rational concepts, whereas the empiricists insisted that all knowledge was a posteriori, that is, after experience, and there were no innate ideas. So that irreconcilable dispute between rationalism and empiricism was one of the key things that Kant addressed.

But first, his approach. Kant's approach to this problem was called the transcendental method. Now, there's some ambiguity in the way in which the term transcendental is used here, but let me try to simplify it for you. Kant looked at the problems that were faced both by the empiricists and the rationalists. He looked at the graveyard of empiricism and the skepticism of David Hume, and it was Hume's skepticism that aroused Kant to try to come up with a reconstruction of philosophy. Kant was a man who lived in Konigsberg in Prussia. He was an obscure professor at the university there.

He never traveled more than 100 miles from his place of birth, and no one ever assumed that he would make any kind of splash in the intellectual world. But he said he was awakened from his dogmatic slumbers by the work of David Hume, and he rose to the occasion out of a desire to rescue science, to rescue knowledge itself. So, his most important and most famous work, The Critique of Pure Reason, was published in 1781, right around the same time that the articles of government for the United States' New Republic were being processed. And we are told in our country that the most significant revolution in the last couple of 300 years was the American Revolution. But historians, of culture, argue that the most significant revolution in the last 300 years was the Kantian Revolution because Kant's new philosophy had far-reaching consequences, consequences that still impact the culture in which we live today. Because if you look at the last 250 years at the last 250 years and see what has happened to the church, see what has happened to the classical synthesis where in the Middle Ages theology was the queen of the sciences, and philosophy was regarded as her handmaiden, and there was a certain intellectual credibility to the truth claims of Christianity.

But since the Kantian critique of the traditional arguments for the existence of God, for example, philosophy has been liberated from theology, and the impact of theology and the church has declined dramatically in the last 200 years. Now, let's again go back to what Kant meant by his transcendental method. He looked at the problems, the problems of truth and how we attain it, and he asked this simple question, not is there such a thing as knowledge, but he said this, if knowledge is possible, what would there have to be in order to make it possible?

In that sense, he's transcending the problem. In that sense, he's cutting the Gordian knot, and he's saying, okay, I don't know whether we can get knowledge or not get knowledge, but if knowledge is possible, how would we proceed, what things would be necessary in order to achieve it? And he said, well, Locke was right and the empiricists were right that all of our knowledge of the external world begins with experience. So, if science is going to be possible, we are dependent, for better or for worse, upon sense experience as our starting point for knowledge. And so, the beginning of knowledge is sensations.

Now, he disagreed with Descartes and the history of rationalists who believe that we are born with certain innate ideas, like Plato argued that we have these ideas with which we're born and all we have to do is stimulate the memory to recall or to recollect those eternal ideas. For Kant, there are no innate ideas, but there are elements that can be called a priori. Remember that technically speaking, the term a priori does not mean before birth. It means before experience. And so, Kant is saying that even though we don't have any content of knowledge at birth, we do have a priori categories that are categories of the mind, categories that make it possible for us to know things before experiencing them.

For example, principles like the law of causality, principles like the law of non-contradiction are not learned from experience. But nevertheless, they are not something that we're born with in terms of a content of concepts, but rather they are rational categories, rational abilities that are built into the mind. So, sometimes people try to diagram Kant's approach to knowledge and speak of his sausage grinder, his sausage grinder epistemology, where there is this funnel at the top where you put the sausage in, and that's the sensation. So, you get these impressions and these sensual experiences, and they go into the funnel of the sausage grinder.

But before anything can come out of the sausage grinder, these sensations have to work through the categories of the mind so that the mind is processing these raw sensations. And not only that, for us to be able to have any meaningful perception of the external world, we always perceive of the external world in terms of things or objects that are in space and time. But do we ever have a sensation or a direct perception of space or a direct perception of time? I was in a conversation just the other day with a young man who was asking me what time was.

And I said, I don't know. I said, we can define it in terms of some kind of motion of consecutive moments or consequential moments or sequential moments. And I said, but I can't conceive of time except by the relationship of motion to something physical.

How do we tell time? We have clocks, a physical object, and we have numbers on the face of the clock, and then we have these different hands moving like the second hand. And I'll often have people stand in front of a clock, and I'll say, it's now 12 o'clock noon, and you see the second hand at the 12. And I said, look down now at the 6. And the second hand is moving towards that second hand.

Here's the 12, and here's the 6, and here's the second hand. And it is moving in this direction. And I'll say, look at the 6, and you're looking at the future. But it hasn't arrived yet, sort of like what goes on in the countdown of Times Square on New Year's Eve when people give the final 10-second countdown. The 6 here remains future, and this hand sweeps down across the dial, and you'll have this sense of anticipation as we get closer and closer and closer to that future moment that is the 6. And then as it comes down here, it goes right past it, and I said, there it goes.

It's gone. That which a moment ago was future is now past. And we talk about living in the present, but the present seems to be hanging there suspended between the past and the future because we can't freeze it. It won't stand still.

It keeps moving. And so how other ways do we measure time? You have water clocks, sundials, sand clocks where the sand is sifting through this hourglass. Every way that we have to tell time in our normal experience is by watching some kind of movement between at least two objects. So for us to have a sense of time, we have to have matter, and we have to have motion. And that always raises the philosophical question, what time was it the day before creation? Remember, Augustine was asked the question, what was God doing before He created the universe? And his reply was, He was creating hell for curious souls. But I mean, people like to speculate about the timelessness of God and the timelessness before time.

Was there time before there was a world and motion? It's an interesting question. Again, we don't perceive it, nor do we perceive space purely because to have a perception of pure space would be to perceive nothing, and nothing is imperceptible. And this was part of the question that Hume was struggling with, if you recall, when he was asking the question, how can I have a distinct impression of a distinct sensation? Why, when I'm standing before of an audience, don't I just experience an inchoate, undifferentiated blob of sensations bombarding my eyes and my ears? How is it that I can distinguish the difference between music and noise? There has to be some kind of discrimination, some ability to sort things out and to perceive these sensations in an orderly way.

Now, is that because there really is order out there, and I'm perceiving an orderly universe, or is it all chaos, and I'm perceiving an orderly universe, or is it all chaos, all cacophony, but as I experience this chaos and all this noise, the noise of the sensation comes into the categories of my brain, am I creating order out of this order as a human being? Well, how is it that I can have a discrete sensation of something in space and time when I have no direct sensation of space and time? Well, Kant said, well, you have to have space and time in order to be able to have a perception. And so he spoke of space and time as what he called pure intuitions. So now we have the rational categories, the empirical sensations, and intuition working in this epistemology. And once we get all through this meat grinder, what comes out the end is knowledge. So, do we know that this knowledge absolutely corresponds to reality?

No, we don't. Now, Kant says instead of defining truth as that which corresponds to reality, Kant declared that truth is a judgment, and he distinguished among different types of judgments, different kinds of judgments, judgments that are a priori, that is before experience, and judgments that are a posteriori, that comes with or through experience. And then he distinguished between two other kinds of judgments, what he called analytical judgments and synthetic judgments.

Now, you recall that we've used this language before. An analytical statement is a statement that is true under analysis. It is true by definition. An analytical statement would be a bachelor is an unmarried man. There's nothing in the predicate that isn't already in the subject so that you know the predicate without ever having to experience it.

It's true by definition. So in that case, an analytical judgment could be a priori, that is without ever experiencing a particular man to see if he's married or not. If you say that the man is a bachelor, you already know that he's not married because the term bachelor means unmarried. Well, working through these, synthetic statements are those statements where we learn new information. The bachelor is rich. Riches don't necessarily coincide with bachelorness, and so you can find a bachelor that's poor or you can find one that's rich, but you can't know whether the bachelor is rich or poor without having an experience of that bachelor.

So far, so good. But he said that there are synthetic statements that are a posteriori, but also synthetic statements that are a priori, and that created a firestorm of controversy among later philosophers because they were arguing that any concrete information must depend upon experience. But Kant, for example, argued that the knowledge that the shortest distance between two points is a straight line. He said, we know that before we're experiencing it. And yet the concept straight line does not have within it the idea of shortness of distance.

It only is a quality of direction. And so the debate goes on. But in any case, all of this is working together to reconstruct philosophy to borrow necessary ingredients from empiricism, necessary ingredients from rationalism, put them together in a synthesis that now makes it possible to proceed. But the proceeding of knowledge is limited only to that arena where we have access by sensation. And herein is the crisis in metaphysics and in theology, which we'll look at in our next lecture.

That was R.C. Sproul on this Saturday edition of Renewing Your Mind, introducing us to the philosopher Immanuel Kant. In his overview of philosophy, Dr. Sproul introduces you to men like Socrates and Plato, Aristotle and Anselm, Marx and more modern philosophers. Request this 35-part overview on a special edition DVD, along with the digital study guide, when you give a gift of any amount at renewingyourmind.org. Your generosity is serving growing Christians around the world who are hungry for sound, trustworthy teaching from the Word of God. This offer ends at midnight, so give your gift and request the consequences of ideas at renewingyourmind.org today. Next time, R.C. Sproul goes deeper in his study of Immanuel Kant's thinking and introduces us to his moral argument. That's next Saturday, here on Renewing Your Mind. you