“As long as I didn’t take the glasses off, yes.”
“And that, Sophie, is precisely what Kant meant when he said that there are certain conditions governing the mind’s operation which influence the way we experience the world.”
“What kind of conditions?”
“Whatever we see will first and foremost be perceived as phenomena in time and space. Kant called ‘time’ and ‘space’ our two ‘forms of intuition.’ And he emphasized that these two ‘forms’ in our own mind precede every experience. In other words, we can know before we experience things that we will perceive them as phenomena in time and space. For we are not able to take off the ‘glasses’ of reason.”
“So he thought that perceiving things in time and space was innate?”
“Yes, in a way. What we see may depend on whether we are raised in India or Greenland, but wherever we are, we experience the world as a series of processes in time and space. This is something we can say beforehand.”
“But aren’t time and space things that exist beyond ourselves?”
“No. Kant’s idea was that time and space belong to the human condition. Time and space are first and foremost modes of perception and not attributes or the physical world.”
“That was a whole new way of looking at things.”
“For the mind of man is not just ‘passive wax’ which simply receives sensations from outside. The mind leaves its imprint on the way we apprehend the world. You could compare it with what happens when you pour water into a glass pitcher. The water adapts itself to the pitcher’s form. In the same way our perceptions adapt themselves to our ‘forms of intuition.’ “
“I think I understand what you mean.”
“Kant claimed that it is not only mind which conforms to things. Things also conform to the mind. Kant called this the Copernican Revolution in the problem of human knowledge.
“By that he meant that it was just as new and just as radically different from former thinking as when Copernicus claimed that the earth revolved around the sun and not vice versa.”
“I see now how he could think both the rationalists and the empiricists were right up to a point. The rationalists had almost forgotten the importance of experience, and the empiricists had shut their eyes to the way our own mind influences the way we see the world.”
“And even the law of causality—which Hume believed man could not experience—belongs to the mind, according to Kant.”
“Explain that, please.”
“You remember how Hume claimed that it was only force of habit that made us see a causal link behind all natural processes. According to Hume, we cannot perceive the black billiard ball as being the cause of the white ball’s movement. Therefore, we cannot prove that the black billiard ball will always set the white one in motion.”
“Yes, I remember.”
“But that very thing which Hume says we cannot prove is what Kant makes into an attribute of human reason. The law of causality is eternal and absolute simply because human reason perceives everything that happens as a matter of cause and effect.”
“Again, I would have thought that the law of causality lay in the physical world itself, not in our minds.”
“Kant’s philosophy states that it is inherent in us. He agreed with Hume that we cannot know with certainty what the world is like ‘in itself.’ We can only know what the world is like ‘for me’—or for everybody. Kant’s greatest contribution to philosophy is the dividing line he draws between things in themselves—das Ding an sich— and things as they appear to us.”
“I’m not so good at German.”
“Kant made an important distinction between ‘the thing in itself and ‘the thing for me.’ We can never have certain knowledge of things ‘in themselves.’ We can only know how things ‘appear’ to us. On the other hand, prior to any particular experience we can say something about how things will be perceived by the human mind.”
“We can?”
“Before you go out in the morning, you cannot know what you will see or experience during the day. But you can know that what you see and experience will be perceived as happening in time and space. You can moreover be confident that the law of cause and effect will apply, simply because you carry it with you as part of your consciousness.”
“But you mean we could have been made differently?”
“Yes, we could have had a different sensory apparatus. And we could have had a different sense or time and a different feeling about space. We could even have been created in such a way that we would not go around searching for the cause of things that happen around us.”
“How do you mean?”
“Imagine there’s a cat lying on the floor in the living room. A ball comes rolling into the room. What does the cat do?”
“I’ve tried that lots of times. The cat will run after the ball.”
“All right. Now imagine that you were sitting in that same room. If you suddenly see a ball come rolling in, would you also start running after it?”
“First, I would turn around to see where the ball came from.”
“Yes, because you are a human being, you will inevitably look for the cause of every event, because the law of causality is part of your makeup.”
“So Kant says.”
“Hume showed that we can neither perceive nor prove natural laws. That made Kant uneasy. But he believed he could prove their absolute validity by showing that in reality we are talking about the laws of human cognition.”
“Will a child also turn around to see where the ball came from?”
“Maybe not. But Kant pointed out that a child’s reason is not fully developed until it has had some sensory material to work with. It is altogether senseless to talk about an empty mind.”
“No, that would be a very strange mind.”
“So now let’s sum up. According to Kant, there are two elements that contribute to man’s knowledge of the world. One is the external conditions that we cannot know of before we have perceived them through the senses. We can call this the material of knowledge. The other is the internal conditions in man himself—such as the perception of events as happening in time and space and as processes conforming to an unbreakable law of causality. We can call this the form of knowledge.”
Alberto and Sophie remained seated for a while gazing out of the window. Suddenly Sophie saw a little girl between the trees on the opposite side of the lake.
“Look!” said Sophie. “Who’s that?”
“I’m sure I don’t know.”
The girl was only visible for a few seconds, then she was gone. Sophie noticed that she was wearing some kind of red hat.
“We shall under no circumstances let ourselves be distracted.”
“Go on, then.”
“Kant believed that there are clear limits to what we can know. You could perhaps say that the mind’s ‘glasses’ set these limits.”
“In what way?”
“You remember that philosophers before Kant had discussed the really ‘big’ questions—for instance, whether man has an immortal soul, whether there is a God, whether nature consists of tiny indivisible particles, and whether the universe is finite or infinite.”
“Yes.”
“Kant believed there was no certain knowledge to be obtained on these questions. Not that he rejected this type of argument. On the contrary. If he had just brushed these questions aside, he could hardly have been called a philosopher.”
“What did he do?”
“Be patient. In such great philosophical questions, Kant believed that reason operates beyond the limits of
