A nice Wittgenstein Web Resource.

I have long wondered how the philosopher Dan Dennett was able to come to think so clearly about the mind. One influence on Dennett and all of modern Philosophy of Mind was Ludwig Wittgenstein. Wittgenstein is often mentioned as one of the most important philosophers of the 20th century.

As a neurobiologist, I was first attracted to Wittgenstein's philosophy for two main reasons. First, when I was starting college I had the idea that it should be possible to sit down at a computer and make a set of programs that would simulate the way humans use language. For each word in the English language I would make a program that, when executed, would determine the meaning of that word for any context within a sentence. Execute all of the programs for each word in a sentence and you would figure out the meaning of the sentence. Within a few weeks of experimentation and research I found that computer scientists had already tried this approach and shown that it does not work. In the spirit of Wittgenstein who liked to leave a certain amount of work for his readers, I will not go into the reasons why it is hard to program computers to understand and use human language. If you think it IS easy, go ahead and try it. Come back in a few weeks when you have seen what the trouble is.

This experience I had (the year was 1977) in learning how truly special human language is, was similar to the experience that Wittgenstein had when he tried to work on the research program of Frege and Russell. Russell (among others) was trying to show that there is a logical foundation for mathematics. This was in the early part of the 20th century when "Hilbert's Program" was very much at the heart of the philosophy of mathematics. There was a long running dispute between philosophers over the possible sources of knowledge:
1) human knowledge (such as mathematical knowledge) all has a "rational" basis. Maybe there is a small set of fundamental ideas and all other truths can be generated from those fundamentals by correct reasoning, by logic.
2) human knowledge is "empirical". Everything we know comes to us by way of our personal subjective experiences of the world.
3) Kant suggested that while there was truth to both #1 and #2 (above), there has to be something more behind human knowledge. Kant suggested that the human brain is like your personal computer......it came from the factory loaded with certain features that determine how human thought works......he called this "intuition".......in modern biological lingo we would call it instinct.
4) And, of course, Kant's thoughts on the subject of knowledge were by no means the last.....the whole "romanticism" movement followed and also had an important impact on Wittgenstein, particularly by way of Schopenhauer.

This idea of "intuition" was different from idea #1 (above) in that Kant did not think that rules for proper reasoning are what constitutes the bulk of our "intuition". Kant was interested in the idea that the human brain is designed to interpret sensory experience in terms of the concepts of space and time......that our concepts of space and time are not something that a tabula rasa could absorb from human sensory experiences. In short, we have to come into the world as biological systems with some built-in structure which leads "automatically" to concepts like space and time......fundamental concepts that are required in order for us to be able to make sense of what our senses present to us. This naturalistic perspective on knowledge had a huge impact on philosophy.......in particular, Wittgenstein eventually came to be heavily influenced by Kant. Wittgenstein tried to take and work with the best that could be found in BOTH
 materialistic theories of knowledge and intuition
AND
 in romantic notions of intuition.

But when Wittgenstein first started learning about how Russell was trying to establish the logical foundations of mathematics, they were both heavily under the influence of rationalism (#1, above) and Hilbert's Program for placing mathematics on a solid foundation........for reconstructing mathematics as an all encompassing formal system where simple logical rules could be faithfully followed to reveal all truth. There were no digital electronic computers and no art of computer programming in the first years of the 20th century, so when Wittgenstein got interested in the idea of trying to find a formal system that could explain human language, he had to use the type of logical calculus that Frege and Russell had tried to develop. Wittgenstein's attempt is described in the only book that Wittgenstein ever published, Tractatus Logico-Philosophicus. Like Kant before him, Wittgenstein thought that he had solved all of the outstanding mysteries of philosophy. One of the key conclusions made by Wittgenstein was that formal logical systems in no way have the power to completely account for the human mind and how humans communicate by means of human language.....the same conclusion that I came to in 1977 by playing with computers. Wittgenstein put it in these terms, "Logical propositions show the logical properties of language but SAY nothing." Computer programs can easily be made that parse sentences to show their grammatical structures, but computer programs that understand the meaning of sentences, programs that could actually say something in the way speaking people do, have not been produced.

The other reason I was attracted to Wittgenstein's philosophy is that I had been told that Wittgenstein was unhappy (he is usually classified as a "critical philosopher") with how both scientists and philosophers study the mind and so he had created his own new way of investigating the mind. Since I am interested in understanding all of the ways that people use to investigate mind, I figured I should try to understand this new system that Wittgenstein had produced.

When Wittgenstein discovered the hopelessness of the rationalist's program of trying to explain human thought in terms of a formal mathematical system, (the Tractatus was published in the early 1920's) he left philosophy behind and became a school teacher. Eventually (late 1920's), Wittgenstein returned to philosophy with a new vision of what philosophy can be. This vision was cryptically presented in the posthumously published Philosophical Investigations. Wittgenstein scholars have been slowly digesting Wittgenstein's more detailed notes which explain many of the cryptic phrases that are found in Philosophical Investigations, and it is safe to say that Wittgenstein correctly recognized the fact that most philosophers of the 20th century would never be able to understand Wittgenstein's vision of a new type of philosophical methodology. This NEWNESS explains why Wittgenstein was reluctant to publish. We can understand that the same thinking process was at work in Charles Darwin, who for many years delayed announcing his discovery of natural selection as a mechanism for biological evolution. Darwin eventually had to publish when Wallace independently discovered the idea of natural selection. Wittgenstein died before anyone else forced him to publish, although he was on the verge of publishing due to the fact that he was a teacher and his ideas were getting into the public world of philosophy by way of the confused views of those ideas held by his former students. This is an annoyance that the reclusive Darwin never had to face. Wittgenstein tried for many years to find a good way to present his ideas in the form of a book, but eventually had to admit that the very nature of the subject matter defeated him.

If you look at the Tractatus, you will see that it fully anticipates what we now know as hypertext.....this fact of form makes the Tractatus very suitable for presentation as hypertext. For the limited domain of the subjects covered in the Tractatus, Wittgenstein's mind was able to grow a tree-like structure by which he could organize and present his ideas. One of the interesting features of biological trees is that the individual branches of a tree seldom fuse with each other to create loops. For the material of the new book, Philosophical Investigations, Wittgenstein could find no way of forcing that material into the limited topology of a tree. What Wittgenstein needed was the complete freedom that is provided by hypertext computer files that can point to each other in endlessly complex loops. Of course, this more complex topology IS the topology of the human brain, and Wittgenstein knew very well that a major challenge for philosophers is the hard work of converting the high-dimensional complexities of the mind into the linear simplicity of human language. So it is unfortunate that Wittgenstein did not simply climb into a time machine during the madness of World War II and come to live in the 1990's when he could have used a PC to present his ideas to the world via the internet and hypertext.

Now, what about Wittgenstein's new type of philosophy? What was wrong with the old types? One major influence on Wittgenstein was by way of Russell's idea that philosophy should be more scientific. Of course, this was not just Russell's idea, a huge segment of philosophy was moving in that direction....it was impossible for philosophers to ignore the successes of science. Another influence on Wittgenstein was the Vienna Circle and Logical Positivism. I think we can trust Carnap's view that Wittgenstein's influence on Vienna Circle has often been overestimated. When Wittgenstein was familiarized with the views of people like Carnap, Wittgenstein knew that he and they differed fundamentally in what they saw as the future of philosophy. The Logical Positivists were devoted to the idea of turning philosophy into a mirror of physics. To do this, they wanted to apply the methods of physics to the problems of philosophy. One method which physicists had adopted was the construction of mechanical instruments by means of which objective measurements of material objects can be made. Physics restricts itself to the construction of physical theories that can account for physical data. As a philosopher, Wittgenstein was devoted to the idea that human subjective experience CAN ALSO provide us with useful data, data about aspects of reality that were outside of the domain of investigation carved out by the physicists of the early 20th century. The Logical Positivists were not ready to accept the human mind as a scientific instrument, so Wittgenstein was really of very little use to Logical Positivism. I think it is likely that the Logical Positivists had more of an impact on Wittgenstein than Wittgenstein had on the Logical Positivists. Logical Positivism, like Russell's earlier attempts to turn philosophy into a formal scientific venture, provided a diving platform against which Wittgenstein could push in order to launch his new type of philosophy.

So far I have tried to frame Wittgenstein's new type of philosophy in the context of the old types of philosophy that he reacted AGAINST. In addition to the movement to put science into philosophy, Wittgenstein was also against an older part of philosophy that we can call "metaphysical speculation and theorizing". A ready example of what features in metaphysics the Wittgenstein of the 1930's reacted against is his own metaphysical theory of language that existed in the Tractatus. Wittgenstein came to realize that the Tractatus theory is too simplistic to do justice to the complexity of language and the human mind. Thus, Wittgenstein learned the hard way, by recognizing the failure of the only book he ever published, that the all too human desire to formulate and proclaim comprehensive theories of mind, thought and language is a human weakness that should sometimes be resisted in the same way humans learn to resist overindulgence in bodily pleasures. There are intellectual pleasures, such as publishing a highly praised book of philosophical metaphysics, that should also be resisted, particularly when one has (maybe in the recklessness of youth) never really taken a close look at the subject matter one is theorizing about. We should look before we leap....even if in academia all the benefits go to those who leap and those who are too cautious are told to go find another way to earn a living. In truth, Wittgenstein may have over-reacted to the short-comings of the Tractatus. In the long run there is really nothing wrong with discovering that an old idea was incomplete.....human ideas breath and grow. In some ways Wittgenstein could not forgive himself for being human.

Another modern invention that Wittgenstein would have loved is the post-it-note. Wittgenstein came to believe that one of the tasks for philosophers was the posting of reminders and warnings for all the places in human philosophical investigations where the human imagination can disengage from contact to the engine of reality and fall into the fantasy land of self-centered metaphysicians where metaphysical theories spin in the breeze like gears that have been blown off of their attachments to the engine of reality.

In much the same way, a major task for Darwin was to find ways to move away from some of the conventional and popular patterns of thinking that existed in Darwin's time. Darwin himself had to leave behind (and also show the rest of the world how to leave behind) the idea of special creation, the idea of static species, and even Lamark's "common sense" theory of evolutionary change by means of inheritance of acquired characteristics. Much of Darwin's effort was focused on refutation of these old bogus ideas, not just the presentation of Darwin's own new ideas.

Now, having set the stage by describing some of what Wittgenstein was against, we can look at what was new and positive in Wittgenstein's thinking. As I mentioned above, Wittgenstein found plenty of ideas that he liked in the work of previous philosophers, ideas that he could build upon. One of the key ideas is usually given the label "intuition".

The ancient Greeks at one time enjoyed the art of trying to explain our world in terms of Fire, Water, Air, and Earth. More modern philosophers play the same game and try to explain the human mind in terms of intuition, experience, instinct, etc., etc. I hope it is clear to everyone that this "modern" philosophical exercise is just as silly as what the Greeks tried to do. However, until the true components of mind are revealed, our Folk Psychological analyses give us something to pass the time.

What did the word "intuition" mean to philosophers like Kant and Schopenhauer? In order to understand this, most people have to temporarily suspend their everyday view of what "intuition" means. If you retain the commonly held view of what "intuition" means, then you will be tempted to make statements like,
 "Intuition appears to be a
 sense similar to instinct, and quite
 possibly there is a relationship between
 the two."
Now "instinct" is a more modern word than "intuition". When Kant was alive, the word "instinct" was not available to him, but as part of his reaction to people like Hume, Kant was very interested in, "experience whose existence depended on prior, nonexperienced mental operations." For example, Kant was able to realize that humans do not come into the world as an absolutely blank slates. A brain comes equipped with built-in ways of interpreting the signals that reach it by way of our senses. This was a major advance in human thought because nobody really knew in Kant's time what a sense organ actually sends to the brain. We now know that the only thing that is sent to the brain is a collection of electrical signals, the action potentials. The action potentials that go to the brain carrying visual information are exactly the same as the action potentials that carry smell, hearing, or touch to the brain. The only way we know the difference between vision and smell is because the action potentials for these different sense modalities go to different parts of the brain where they are interpreted by the brain in different ways. To the modern mind that knows the basics of neurophysiology, Kant's philosophical position is not amazing, but in Kant's time, most philosophers were either rationalists who believed that we reason our way to a proper view of the world or they were empiricists who thought of the brain as a kind of wax block that simply and passively takes up the impression of sensory phenomena. When Kant recognized a role for "nonexperienced mental operations" in determining how our minds interpret sensory inputs, he was WAY ahead of his time. Only slowly have philosophers come to accept the idea that the unconscious part of brain activity predominates over the conscious part of brain activity. In Kant's time (and right up until today, in many cases) philosophers were reluctant to believe that there are things going on in our heads that are invisible to rational thought, introspection, and personal experience. Some modern philosophers such as John Searle still want to DEFINE mind as what is visible to rational thought, introspection, and personal experience. This is a great example of the momentum within philosophy to keep looking at old problems in the same old ways.

Here is an example of a human instinct. Some human females exhibit "nesting behavior" before giving birth. For example, a woman may suddenly feel compelled to clean their entire house from top to bottom. It is not a rational urge. A few days later she gives birth. Now people do not LIKE the idea that their behavior can be "mindless", automatic, pre-programmed by their genes. But we should not return to the biases that were unquestioned when held by pre-Kantian philosophers. Kant was concerned with the idea that our brains might impose what we experience as the structure of space and time on our raw sensory inputs. Again, Kant has been totally vindicated by modern brain science. Our somatosensory perception involves a map of the human body in the structure of the cortex. The visual cortex contains several copies of a spatial map of the external world. The formation of these brain maps is complex, but it is safe to say that the human brain is designed to construct these maps during normal development, then they function throughout our adult lives as inescapable (unless the brain regions containing them are destroyed) constraints on how we interpret the world. These constraints are entirely invisible to us, and Kant only discovered their existence by an exercise in logical deduction......he reasoned that they had to exist in order for any system to be able to interpret sensory input. This is entirely analogous to the way that Darwin reasoned that some mechanism had to exist that could generate the diversity of life. Of course, the process of biological evolution is just as invisible as the circuitry of the human brain, so Darwin had to indirectly deduce the properties of the mechanism we now know as natural selection. Darwin was vindicated by later discovery of DNA and mutations. Kant's philosophical insight into the nature of human knowledge was vindicated by opening up the brain and seeing the organization that exists there because of our genetic heritage.

So it is safe to update Kant's terminology and admit to ourselves that while Kant is traditionally translated as having wrote about "intuition" functioning as a guide for how we interpret our personal experiences, what he was really talking about was how instinct guides us towards knowledge of the world. Now Schopenhauer wanted to take this fundamental insight into the human mind and expand on it. The tradition within philosophy was that it is best to do philosophy by logical, rational, and analytical means. Schopenhauer, rather than accepting this tradition, tried to point out that within philosophy, reason is usually faulty, leading philosophers down blind alleys. Schopenhauer was able to see the fact that when people know things about the world, they almost always obtain that knowledge independent of logical, rational, and analytical means. Even if you look at the successes of philosophy (or science), you realize that the great discoveries are usually made by "leaps of imagination" and "sudden insight".....only after the fact does the discoverer get around to the task of describing the discovery in linear language and the task of trying to rationally justify the discovery by a logical chain of reasoning. Schopenhauer taught that the human mind contains totally unconscious systems by which our minds are able to use "intuition" to allow us to correctly attribute mental effects to external causes. We have an instinct that prompts us to attribute elements of our brain's activity to a model of reality in which there is an external world of objects surrounding us. Wittgenstein was completely accepting of this Kant/Schopenhauer view of how our minds function, so Wittgenstein was able to commit to doing philosophy in a new way, a way that is accepting of our innate and unconscious intelligence. However, Wittgenstein rejected Schopenhauer's extreme solipsistic view about the World as Will. Schopenhauer's extremism is instructive because it shows the logical extreme that can be reached if a philosopher indescriminantly and all-inclusively applies the "intentional stance" to the objects of our personal conscious experience. By participating in psychological experiments, Wittgenstein knew that human consciousness and Will do not have complete control over our minds, let alone the entire world.

Now we immediately run into trouble if we follow Wittgenstein down this path. When we recognize that the unconscious part of our mind is ESSENTIAL for the function of the human mind, the generation of human knowledge, and the power of human language.....if we accept that.....then what are we to do about it? How do we deal with the unconscious part of the human mind? The first problem is that classical philosophers and scientists all want to ignore the unconscious. So you have to deal with the huge cultural momentum that is biased against what you want to do. The second problem was that there were some new-fangled philosophers and scientists who were starting to probe the unconscious, but they were doing it ALL WRONG. Within philosophy there were "phenomenologists" who were trying to figure out how to go about the task of analyzing the elements of personal experience and they were constantly running into the problem of the invisible boundary between the conscious and the unconscious. How can you make a "science" out of personal experience when the elements of experience keep popping into and out of our awareness? Within "science" there was the wild world of Dr. Freud. Freud was the first "scientist" to entirely accept the existence of the unconscious and he imagined that the unconscious part of the mind is populated by alternate personalities of the same level of complexity as our conscious selves. This multiple personality model of the mind was far beyond the "stupid" mechanisms that can be built into brains as instincts. So how was Wittgenstein to not only explore the unconscious side of thought, language and mind but also avoid the bogus pseudo-scientific approaches that were then being developed by others?

Now there are those who will claim that Wittgenstein was a phenomenologists, but Wittgenstein did not adopt the terminology and methods of the phenomenologists. In particular, although Wittgenstein was very much concerned with personal experience, he was intellectually involved with personal experience in the same way that young boys are often interested in swimming suits and bras......they are REALLY interested in what is under the clothing. Wittgenstein had a keen sense of figure and background. He often said that what was most important about his work was what he left out and left unsaid, as if what was missing was what really defined his work. I think it is also the case that Wittgenstein's method of philosophical investigation came to be centered on what is normally invisible to introspection and how we might work to bring the invisible features of the mind into view. Part of that research program involved trying to be certain about what IS accessible to us in our personal experience......this can provide a way of tracing out the boundaries of the negative space consisting of what is not accessible to personal experience.

Now, as a biologist, I am interested in the idea that neuroscience can bring the unconscious part of the mind into focus. However, I am very interested in the way Wittgenstein tried to use introspection to cast light on human "intuition" (again, I use "intuition" in the Kantian sense, described above). I think Wittgenstein was working with data that have too long been ignored by neuroscientists. We really need to try to bring Wittgenstein's Philosophical Investigations in to balance and a state of unification with the modern materialistic view of the mind.

A major part of Wittgenstein's philosophical work centered on an analysis of human language from the perspective of how human language behavior is an integral part of human life. Wittgenstein had no interest in attempts to study either ethics or language in the abstract, disembodied way favored by other philosophers. Wittgenstein's approach is thus a form of naturalism in that it respects the form of life that makes human language behavior possible. Much of Philosophical Investigations is devoted to examples of how philosophers can miss-use language. What Wittgenstein wanted was for readers of Philosophical Investigations to use that book like a work book. Wittgenstein provided a large number of examples and exercises by which the reader can be shown how to experience the complexity of mind, thought and language and the common ways in which philosophers ignore that complexity and quickly find themselves using language to "do no useful work" and detach themselves from reality. There is a huge secondary literature on Wittgenstein, the Companion to Wittgenstein's 'Philosophical Investigations' by Garth Hallett is a good place to start for guidance, but what you really have to do is pretend you are sitting with Wittgenstein as he tries to show you how to explore your own mind.

Philosophers accept the idea that, "an unexamined life is not worth living." However, what can philosophers DO when the tools required for examining life are not available? Philosophers tend to go at the job with whatever tools are at hand. One tool that philosophers make heavy use of is language. Wittgenstein was among the first philosophers to try to examine language itself. One of his main conclusions was that philosophers, in taking language for granted, had gotten themselves into the habit of trying to make language do work that it cannot do.

Mathematical logic was the tool which Wittgenstein first turned upon language in order to begin to examine language. Initially, Wittgenstein had the hope that logic could cure the ills that arise when philosophers use language.....maybe all we have to do is use the tools of logical reasoning in order to put language use on a firm a