Does Kant Rescue Cause and Effect from Hume?

Perhaps the stickiest wicket that Kant faces in his Critique of Pure Reason is to roll back Hume's argument that there ain't no such thing as cause and effect.  For Hume, all we can say about events in the world is that B follows A.  We can never say that A caused B.

Since the Brits invented cricket, you can see that the German Kant would have to be really on his game to deal with the googlies from bowler Hume.  (Although I don't know if googlies had been invented yet).

In a way, Kant's whole transcendental machinery is designed to deal with Hume's challenge: what warrant can there be for any assertion of A being the cause of B?  The whole idea of the external experience of objects as appearances rather than things-in-themselves is the center of Kant's cunning plan to deal with Hume and his tricky bowling.

Kant makes his argument that, for any experience in the world, there must be a rule that predicts the occurrence of an event from a previous event, for if there were no rule in the mind connecting events then indeed all sequences of perceptions would be merely subjective, received impressions having no connection with any outside object.  On that view there would be no way to cognize any outside object.

The cunning trick is, of course, that we are not talking about events-in-themselves or outside-objects-in-themselves.  The events are appearances, impressions that the mind processes into unified judgments about what is going on out there.  If I see a boy in the neighbor's yard in the act of throwing a baseball towards my house I take note of that appearance.  If half a second later I receive the impressions of a crash and tinkle in the front room and a a boyish squeak from the neighbor's yard, I am justifying in applying a rule that baseballs thrown at my house are quite likely to hit my house and that the appearance (or hear-ance) of a crash and tinkle shortly after the appearance of the neighbor boy and his baseball justify my judgment that it was the boy wot done it.

It all revolves around the appearances vs. things-in-themselves game.  In the game of appearances I could always be wrong.  It's possible that I didn't see the other kid across the street and his baseball.  Or it could be that a meteorite came out of the sky and broke my window.

But none of that matters.  What matters is that Kant's transcendental machinery describes how my sensibility receives impressions from the outside world, which I process in accordance with my forms of intuition about space and time and then combine them into a manifold using the categories of understanding.  Then I apply judgement to bring the manifold to a unified experience of possible external objects of experience.  But those objects are only appearances, not things-in-themselves.

Good old Kant.  Gin clear, as always.  And four runs for the Königsberger against the best bowling in England.

Kant's Problematic Refutation of Idealism

Immanuel Kant came up with a wonderful idea.  Let's just say, he writes, that we can't see things "in themselves" but only as appearances.  In that one idea he elegantly avoids claiming that we can ever know the whole truth about life, the universe and everything.

Kant's idea is, of course, not much different from St. Paul's talk about seeing through a glass, darkly.  And it is echoed by the quantum mechanical dictum that you can't see anything in the sub-atomic world without disturbing it.  So you do not see an item "in itself" but only after you have nudged it, with some kind of electromagnetic or sub-atomic energy.  So whatever you are looking at, it is not the same as it was.

But Kant feels the need to demolish his predecessors with his Refutation of Idealism.  He wants to dispatch the Dogmatic Idealism of Berkeley and the Problematic Idealism of Descartes.

Problem is that most everyone agrees that Kant doesn't quite pull it off, thus violating the first rule of politics that if you come to overthrow the king you had better succeed.  Or else.

Kant wants to refute the Cartesian idea that the outer world is "doubtful and indemonstrable."  Kant crosses over Descartes' division between knowledge of internal and external states by setting out to prove that the "empirical consciousness of my own existence proves the existence of objects in space outside me."  Kant's argument is based on the idea that I am conscious of my existence in time and the presupposition of something "persistent in perception" and so on.  

The commentators all seem to agree that Kant doesn't finish the job.  Actually, they begin with contesting the first premise of his proof: "I am conscious of my existence as determined in time."  They say he doesn't even start the job of refutation properly.  

Even a tyro like me can see the problem.  Way back in the Transcendental Aestshetic Kant declares that time is a form of intuition that resides in the mind.  So we are using an intuition cooked up in the mind to argue for the existence of the real world?  Come on Immanuel.  You can do better than that!  You are really arguing Descartes' point that the only thing we can be sure about is the thinking "I"!

Really, Kant should stick with the beauty and the elegance of his central creative insight.  We can't know things in themselves.  Everything we know about anything (including our internal self) is founded on belief.  We believe in an "I"; we believe in an external world.  And until our brains start to rot in old age, that belief seems to work for us.  It gets us food, shelter, and a new generation on the ground and out of the nest.  

There's a refutation of idealism for you: grandchildren!

Kant and "Dogmatic Idealism"

Kant set himself a big task in his Critique of Pure Reason. It was not perhaps as big a task as that of the Rev. Edward Casaubon in his "Key to All Mythologies," but big nonetheless.

Kant wanted to spike Descartes's skeptical idealism, that the "I" was indubitable, but the world not so much. He wanted to whack Berkeley for his dogmatic idealism that the world was an illusion.  But he also wanted to deal with Hume and his denial of cause and effect.  Never mind that he also had a mind to derail the whole global industry busily proving that God existed, not to mention the rapidly growing atheist startups aggressively insisting that God didn't exist.

Common sense tells us that the world exists; that's what Dr. Johnson insisted by kicking a stone with his foot and saying of Berkeley's idealism "I refute it thus."  Common sense tells us that every effect has a cause, even if we didn't see the cause coming before the effect.  So somehow those clever Dicks had to be wrong.

Now you might think that Kant was also a dogmatic idealist.  After all, his repeated insistence that we do not know things in themselves but only appearances suggests that we do not have knowledge of things in the outside world.

I prefer to interpret Kant as setting out the first modern attempt to figure how our mind/brain actually deals with the outside world.  He does this by accepting (even as he insists he refutes) the positions of his predecessors.  Yes it's true that we cannot be too certain about the outside world (Descartes) and that it could all be an illusion (Berkeley) and that cause-and-effect is a tricky business (Hume) especially if you get the cause for an effect wrong.  So what?

So Kant sets up what we would call a "model" of the way that humans deal with the outside world, whatever it really is.  We possess "sensibility", the "capacity... to acquire representations" from the outside world.  From the representations we form "intuitions" based on the forms of intuition inside us about space and time.  We apply the categories of the understanding to our intuitions and then form a unified judgment about the result through the power of "apperception" or self-consciousness.  This judgment is made about the object given in sensibility, its appearance as conditioned by our intuition our understanding and so on.  But what the object really is, in itself, can never be known to us.

It all comes down to common sense.  We know, if we know anything, that we should never assume that we have nothing left to learn, that we have grasped the complete truth about life, the universe, and everything.

Because the moment that you figure you have everything figured out, the world will refute you, "thus."

Can Kant Comprehend Sub-atomic Particles?

Kant's transcendental philosophy is an odyssey between the Scylla of rationalism and the Charybdis of empiricism.

He does not deny that thoughts are real, or that the world is real.  He just says that we cannot know the world as it is in itself.  We can only know appearances.  Our knowledge of the world is constructed upon the way that we manipulate and synthesize sensation into a unified object of experience.

But what about quantum physics?  The recent discovery of the Higgs boson was predicated on the statistics of the recording of certain energetic events on certain detectors at a government-funded particle accelerator designed especially for the discovery of the Higgs boson.  Does that count as sensation?

Locke speculated about a "microscopical eye" that could  see into the "secret composition and radical texture of bodies".  And Kant in the Architectonic of Pure Reason talks about the limited reach of an idea, for the elaboration of the idea into a scientific schema "seldom corresponds to the idea; for this lies in reason like a seed... hardly recognizable even under microscopic observation."

But does the gigantic apparatus of a particle accelerator boil down, in essence, to a microscopical eye or a microscopic observation?  Is the experimentation of modern physics contemplated by Kant's transcendental machinery?  He says that the "capacity (receptivity) to acquire representations through the way in which we are affected by objects is called sensibility."  Does sensibility extend to the eye reading the report on the statistics prepared by a team of physicists detailing six months of particle collisions in the Large Hadron Collider at CERN in Geneva?

So if we accept the results of the physicists, does that make the Higgs boson an "object of possible experience"?  Here, of course, we are getting beyond individual experience to the notion of science as the project of a social community of scientists, as divined by Thomas Kuhn.

The larger purpose of Kant's first Critique was to deal with the conundrums arising from Descartes, who thought that the "I" was indubitable but the world was dubitable, to Hume who argued that knowledge was a rickety construction built on a bundle of impressions, to the impossibility of proving God's existence on reason alone.  Yet here we were in Kant's time with science burgeoning and generals using the results of science in their very real artillery.  Kant built the first detailed analysis of human cognition, recognizing it as what we would call a feedback loop.  Objects act on us through our sensibility and we form judgments about objects as objects of possible experience.  But we do not know them as they are in themselves.  We only know them as they appear to us and as we think them.

Perhaps the greatest achievement of modern science and technology is how they have changed the way that objects can act on our sensibility.  Years ago I remember watching a TV science program in which they showed how human objects on a beach appeared in different forms of light, from infrared to ultraviolet.  Things look very different when you illuminate them with different light.  And how really do they look "in themselves?"  All we know is how they appear to us, as illuminated to us.  A snake has infra-red detectors, all the better to detect warm-bodied mice in the nighttime.  Why not?  Sense organs are not there just for the contemplation of the ineffable; they are there for survival.

Of course Kant didn't predict everything.  But he did set the stage for us moderns.  Don't think that what you see is what you get.  The "thing-in-itself" may be very different from its appearance.  If indeed there is such a thing as the "thing-in-itself."

The Paradox of the Enlightenment

At the core of Immanuel Kant's great attack on his philosophical predecessors, from Descartes to Berkeley and Hume, is the great Paradox of the Enlightenment.

Here we had the most stunning development in human thought, Newtonian mechanics, that showed how us how the world worked.  Yet against that we have Descartes saying that "I" can't be sure of the external world, Berkeley saying that the exterior world is an illusion, and Hume saying we can't be sure about cause and effect.

Just when Newton has reduced the operation of the external world to a few equations that allowed, e.g., artillery officers to predict where artillery shells would land, the philosophers said: Don't get cocky, kid.

One of the places in in Critique of Pure Reason where Kant really concentrates his fire on his predecessors is in the "paralogisms," i.e. the logical mistakes of his predecessors.

In the Fourth Paralogism, Kant takes on the doubtful existence of outer reality, the real world.  In the first edition, Kant put the paralogism this way.  Things that can only be inferred from perceptions are doubtful.  All outer appearances are inferred.  Therefore "objects of outer sense" are doubtful.

In the second edition, Kant takes a different tack in a rather confused paragraph (B409) that already assumes the error.  He seems to be arguing against this syllogism:  I am distinguished from things outside me.  Other things are those that I think of as distinguished from me.  Therefore I exist as a thinking being.  Or maybe not.

But Kant drills a hole in this argument before he makes it, for by the second edition he can't be bothered too much about making the arguments of his predecessors.  His point is the Great Argument of his entire critique.  If I am confident that the "I" exists, then how could I know it without experience of the outside world?  For against Descartes, Kant argues that we cannot have any knowledge of ourselves apart from our moment to moment experience of self-consciousness as we deal with and process data given to our senses, and try to make sense of it.

Kant's "I" is a component in the human machinery that receives sense impressions, combines them with forms of intuition, gathers the sense impressions and intuitions with the categories of the understanding and creates, using the "I" of apperception (self-consciousness), a unified object of appearance, a judgment about the outside world.  And don't forget that this object in the outside world can only be known as an appearance, not as a thing-in-itself.

If you think about the world like Kant, then all the mind games about mental substances and material substances, the indubitable I and the dubitable outside world, all these things fall away, because they are all integrated together into what we would now call an OODA loop.

Notice that if you subtract the "I" of self-consciousness from Kant's machinery, then you still have a working model of existence in the real world, but one that applies to the "lower" animals.  As far as we know, they get their sense impressions and unify them with intuitions and categories of the understanding.  What they do not do is then apply reason to their unified understanding to get to judgment.  Their judgment is hard-wired rather than flexible.  So they operate in the real world without an I at all, but instead, as we highly advanced humans suppose, in an egoless flow of consciousness.

Since Kant's time, of course, the Paradox of the Enlightenment has increased and deepened.  For now we may know much more about the sensible world, and even in the interior mental world, yet we know less and less "what it's all about."

Why We Need Intuitions AND Concepts

OK, says Kant in the first Critique.  You could say that appearances that we get from our senses chunked together with intuitions are all there is.  Just as Hume suggests with his "associationism."  That's the point of his setup before the Transcendental Deduction:

Appearances might very well be so constituted that the understanding should not find them to be in accordance with the conditions of its unity.  And everything might lie in such confusion that, e.g., in the succession of appearances nothing would offer itself that would furnish a rule of synthesis and thus answer to the concept of cause and effect, so that this concept therefore would be entirely empty, nugatory, and without significance.  Appearances would nonetheless offer objects to our intuition, for intuition by no means requires the functions of thinking. (B123/A90)

Sorry to punch all that out, but it's important.  Kant here is making Hume's argument.  Hey, maybe our mind just gathers up appearances in a bundle and reads the patterns therein.  So maybe we just note the patterns and say, wow, there's a pattern here!  First the sun rose yesterday, and then it rose today!  Maybe there's a pattern here.  No need for analysis; no need for thinking; no need for concepts.

But Kant cannot accept this.  When we "cognize" an object, he claims, we do more than make a reactive burp in response to sense impressions.  And  so he lurches into the Transcendental Deduction to prove that we synthesize our bundle of intuitions using the forms of intuition in space and time and concepts derived from the categories, and then we unify the synthesis into a judgment about an object in an act of apperception, of a self-conscious validity claim.

Kant calls this objective validity, which is a bit of a push, since he's talking about a "valid" cognizing of a unity of synthesized intuitions with the help of the concepts of the understanding into a unified "object."  The notion of "objective validity" is obtained by calling things by the conveniently right names.

For us, the interesting thing about Kant's argument is its foreshadowing of the modern approach to reality.  Kant is claiming that we are not really passive consumers of appearances, but purposeful actors.  We take the stuff coming in over the transom and organize it in our minds in a strategic effort to understand and judge what is going on out there in the tough and challenging world.  We process our sense data and then construct in our minds a picture of what we have seen.  We "think" what we see and advance our claim of what we have seen and what we judge we have seen.

Forget Hume, Kant says.  I offer you a whole new world of active, purposeful "cognizing."

Kant's Best Shot: "Objective Reality"

In the Transcendental Deduction, Kant hauls out his big gun against Hume's "associationism:" he calls it "objective reality."  The idea is that if you run your lumber through Kant's three-stage lumber mill, inserting raw logs of sense impressions into the circular saw that slices the sense impressions through the forms of intuition, and then you assemble the manifold of resulting log intuitions into the synthesis of a stacked pallet, then you can judge the resulting stack of Grade A two-by-fours as a "necessary unit of the apperception in the synthesis of intuitions."

Why is this objective?  Because writes Kant, "[the] transcendental unity of apperception is that unity through which all of the manifold given in an intuition is united in the concept of the object.  It is called objective on that account[.]"(§18, B140)  Get it?  Since the thinker has united his manifold of sense impressions into a unified single object, he now has an objective reality.  The "subjective unity of  consciousness"  (Hume's association) is merely a "determination of inner sense" without the uniting into a single object.

So while we have merely a bundle of sense impressions we don't have a unified object, and therefore no objective reality.

What Kant seems to be trying to argue is that an objectively valid judgement is one that makes a claim, an assertoric judgment, as "this body is heavy."  This is a claim that can be agreed to or denied by others.  The statement that "bodies and heaviness seem to go together," i.e., a weaker claim than Kant's phrase "If I carry a body I feel a pressure of weight" comes closer to the Humean idea of a bundle of impressions.

But really, it seems to be much more sensible to accept Hume's skepticism that you can never really apply objective criteria to a truth claim about an association, and move to modern neo-pragmatism and say that look, the science is settled on this, at least a low velocities, so we know, from our concepts of the understanding, that bodies are heavy and bodies of gold are really heavy.  Until someone proves us wrong.

"Thoughts without content are empty"

It's one of the most quoted zingers in Kant's Critique of Pure Reason.

Thoughts without content are empty.  Intuitions without concepts are blind.

OK.  So what is the chap talking about?  Kant's whole game is to deal with the David Hume challenge, his so-called "associationism."  On this view we humans are more or less passive consumers of a bundle of sense impressions of the real world.  Kant's strategy is to turn this on its head.  No we don't associate sense impressions with the real world.  We take formless sense impressions, view them with the forms of intuition about space and time, synthesize them with intuitions, and then own them as ours by applying the pure concepts of the understanding to our intuitions and finally applying judgments.

The experts call this the "togetherness principle."  You need both concepts and intuitions to achieve useful judgments about the world as it appears to you.   Kant repeats his famous apothegm several times:

• "[N]either concepts without intuition corresponding to them in some way nor intuition without concepts can yield a cognition."
• "Thus pure intuition contains merely the form under which something is intuited, and pure concept only the form of thinking of an object in general."
• "Without sensibility no object would be given to us, and without understanding none would be thought."
• "The understanding is not capable of intuiting anything, and the senses are not capable of thinking anything."

All along, Kant is arguing for the importance of both intuition and concepts in full human cognition.  Thus, Kant might have made things clearer had he written:

Thoughts without sensible content cannot apply to the real world; intuitions without rational concepts cannot be used for judgment.

For all its famous difficulty.  Kant's Critique does have its moments.

Are Space and Time Real?

We humans are born, live, and die, and experience ourselves moving through time.  We open our eyes and see objects before us.  It seems sensible to see space as a container, as Plato did, and time as the flow of a river.  But are they real?  Can we speak as Newton did of absolute space and time?

The early modern era brought these questions into sharp relief, and by the time that Kant came along there were several contesting notions abroad, from Newton's absolute space and time--though he insisted that humans could only experience relative space and time--to Bishop Berkeley's idealist notion that we cannot experience absolute space and time and so should content ourselves with experiencing sensible things.  For Hume, impressions come before ideas, so space is our interpretation of a bundle of impressions that seems to suggest extension.

Kant's Big Idea is to drive his ship between the Scylla of absolute space and time and the Charybdis of external impressions.  He doesn't want to prejudge the world as real, for Berkeley shows that our ideas of the world are all in the mind.  But he doesn't want to concede to Hume that the world imprints itself upon us.  Thus for him space and time are forms of intuition independent of experience.  They form a mental framework, forms of intuition, that the mind uses to make sense of sensible impressions.  Says he:

By means of outer sense [i.e. physical sensations of external objects]... we represent objects as outside us, and all as in space.

But he argues that the "representation of space" can't be obtained from experience but rather that "outer experience is itself possible only through this representation."  We do not get our experience from outside; we manufacture it inside us, and only then apply it to the outside world.

This is a theme that repeats itself again and again in Kant, and you can see that it comes down to us in current notions of the way that science works.  You have a problem, so you gather some data.  Then you come up with a theory in your mind, a mental idea of how the world works.  You test it against the data.  If it works, your mental idea is your new view of the world.  Until your wonderful theory crashes and burns and another theory comes up and supersedes it.

Now Kant does not consider space as an illusion, existing only in the mind.  He argues the reality of space for "everything that comes before us externally as an object."  But he insists on the "transcendental ideality" of space when we are talking about things in themselves.

When it comes to time, Kant asserts that "time is nothing other than the form of inner sense, i.e., of the intuition of our self and our inner state."  And it is a necessary condition of our experience of space as well, because we could not experience external objects unless they were experienced in time.

Again, Kant asserts the "empirical reality of time" an an objective reality of all "objects that may ever be given to our senses."  But not "absolute time". That "transcendental ideality" could "never be given to us through the senses."

Kant and Copernicus

There's a sad truth about books with brilliant theories that change the world.  They often don't even cause a ripple, not at first.  And the audience for the book, the educated elite, sneers at it.

That's what happened to Kant after the publication of A Critique of Pure Reason in 1781.  Poor chap!  Here he had reformulated the whole basis of western philosophy and all he got for it was a few crank calls.

But the dear old chap set to work.  He published in 1783 the Dummies version of the Critique, a Prolegomena for Any Future Metaphysics.  Then in 1787 out came the heavily revised second edition of the Critique of Pure Reason.  It's in the preface to the second edition that Kant makes a bid for world domination.  Copernicus, he writes,

when he did not make good progress in the explanation of the celestial motions if he assumed that the entire celestial host revolves around the observer, tried to see if he might not have greater success if he made the observer revolve and let the stars at rest.

 Yeah, Manny.  Why not compare yourself with the Great One!

Kant's revolution is a little different from the Copernican revolution.  He's not concerned with the motions of the planets.  He just wants to know how we cognize the world.  As he says: "up to now it has been assumed that all our cognition must conform to the objects" but all our efforts on this line have "come to nothing."  So let's do it the other way around, he writes.  Let's assume "that the objects must conform to our cognition" on the view that our minds organize the world using "categories" to interpret the appearances of the world, so establishing "something about the objects before they are given to us."

One of the rewarding things about studying chaps like Kant is to see how these brilliant pioneers are getting the first fuzzy view of what the average bear takes for granted today.  In Leibniz we get the idea of "monads" which are non-visible elements of everything but which cannot be directly experienced.  That's an wonderful guess at our modern idea of "quanta" that we moderns have cognized using the penetrating power of what Locke called "microscopical eyes" and we call particle accelerators.

Then Kant, with his idea that the mind organizes reality according to categories formed in the mind, brilliantly prefigures modern knowledge about the brain and the way we organize the impulses coming into our brains from our senses.  I remember seeing a documentary as a kid where they gave people "upside-down" eye-glasses that made everything look upside down.  After about a month, the brains of the test subjects inverted the image the subject saw.  So then, if they took off the glasses, the world looked upside down again.

Then, of course, there is Noam Chomsky's idea that we are already programmed to do language before we start to speak.

Kant's brilliant step is to say: look, let's stop worrying about what the really-real is like.  Let's just think about how we experience the world and function in it.  Let's not worry about "things-in-themselves" when the only thing we know is what we experience, the appearances that we organize in our minds.

Today, two centuries after Kant, the latest "truth" about the really-real is that the universe is completely empty, except for tiny dots.  And the tiny dots turn out to be almost empty except for tiny nano-dots deep in the middle of the tiny dot.  The solidity that we experience with our eyes is just electromagnetic radiation in the "visible" part of the spectrum thrown off by pesky electrons fuzzing around a tiny dot.   If you illuminate an object with, e.g., X-rays, you see something completely different.

Of course, just as Marx turned Hegel upside down, converting Hegel's idealism into materialism, so Kant turned Copernicus upside down.  Copernicus said let's stop putting the observer at the center of the universe and put the sun at the center instead.  Kant said let's stop putting the objects out in the world at the center of our world and put the individual a priori cognition at the center of our understanding of the objects out in the world.

Hey, whatever floats your boat.