Since many of Polanyi's main ideas in the book are given in other reviews, I thought it might be helpful to mention some other figures that are often associated with Polanyi so as to provide more of a context for his thought. First, the philosopher Marjorie Green, acted as Polanyi's interpreter to the philosophical community while he was alive. Her most accessible work is called The Knower and the Known. She did think that toward the end of his life he started to change some of his ideas (for the worse according to Green) although my cursory reading of the issues surrounding this claim have led me to conclude that it is mostly phiosophical hair-splitting. I consider Thomas F. Torrance, theologian and former moderator of the Church of Scotland, to be Polanyi's best living interpreter. He is particularly important to understanding trends in theology that have been influenced by Polanyi's thought. Most helpful is a long article that was published elswhere but is now found in a book called Transformation and Convergence in the Frame of Knowledge. Torrance does an excellent job of comparing Polanyi to the another big name in epistemology, namely Karl Popper, arguing that Polanyi's views are more inclusive and therefore superior. Some instructive comparisons between several seemingly disparate figures such as Kierkegaard, Piaget, Einstein, and Torrance can be found in a book entitled The Knight's Move by Loder and Neidhardt. I think someone has also mentioned it but Everyman Revived really is a nice little summary of Polanyi's main ideas. If you are a philosophy student you must read Personal Knowledge as it is the magnum opus of a very influential but often little recognized figure in the history of epistemology and the interface between science and philosophy.

"Personal Knowledge" by Michael Polanyi is still a valuable contribution, even now.

"Magellan" has said that subjectivist investigations don't buy you much anymore, but consider this:

Objectivist investigations don't tell you anything about how to use your own mind- the only tool you have for understanding Science to begin with. Yes, our brain is incredibly complex- yes, it has scientifically-investigatable structures which may be responsible for our consciousness- but without the actual, unavoidably personal use of your brain, you have nowhere to begin. I have all the structures that Magellan discussed in my brain, serving me at this very moment- but their function is underneath even what Polanyi calls "subsidiary knowledge". We can be aware of how our mental processes appear to behave to our conscious mind, but we are not aware of the work and usage of our individual neurons. If Magellan can show me how to become aware of the individual structures in my brain with all their individual neurons, and consciously micro-mangage their function in a way that results in me obtaining a better understanding of the world than I have only through the subjective perspective of my conscious mind, then I will say Polanyi is useless.

Until then, exclusively Objectivist investigations of the conscious mind won't buy you much, in terms of understanding how you (necessarily working out of the perspective of your own state of consciousness) comprehend the world we live in. If you want to learn something, anything, from science-- and still retain a sense that you can legitimately use your own subjective mind (albiet carefully) as you learn-- then it is worth reading Polanyi.

I don't think much of personological/subjective explanations of science, such as Kuhn's and Polanyi's, but I think their views should be heard and considered nevertheless. Western writers seem to have an odd fascination with this sort of approach, for reasons that are understandable historically but that I believe are still untenable, most of which is related to the west's obsession with the individual ego and individual consciousness and with the phenomenological and existential approaches to reality that grew out of that.

While I respect Polanyi as a scientist (he was a noted physical chemist), unfortunately I think he's pretty much gone off the deep end in terms of his subjectivistic interpretation of scientific method and of the work of the scientist, which amounts to a form of neo-Kantianism.

The first problem I have with this is that by making the human mind the final arbiter of all knowledge and sense data, a systematic ghost of an illusion pervades Polanyi's, and indeed, all Kantian theories, because there is no strong connection to external reality anymore. While I would agree with Polanyi in regard to Kant's basic thesis, that the mind is actively involved in organizing the data of the senses, and that ideas about the external world could not exist unless there were corresponding mental capabilities and constucts to match, this idea, although fine for its day, really doesn't buy you much anymore in my opinion. This is for two reasons, which is the problem of illusionism which I just mentioned, and the second is the approach that has now emerged from the last 75 years of work in neurobiology and the brain sciences, of which these writers seem blissfully unaware.

Although we still have a lot to learn, the picture that has emerged so far is both fascinating and impressive. For example, there are 60 trillion cells in a human brain organized into 14,000 major and minor brain centers, and they are all networked together. Each individual neuron has between 3,000 and 100,000 connections with other neurons, producing a neural web of unbelievable complexity.

Most sensory neurons are devoted to using feature-detecting algorithms that require advanced calculus to understand, as David Marr has shown. For example, to mention just a few of his important ideas, Marr's demonstrations that retinal receptive field geometry could be derived by Fourier transformation of spatial frequency sensitivity data, that edges and contours could be detected by finding zero crossings in the light gradient by taking the Laplacian or second directional derivative, that excitatory and inhibitory receptive fields could be constructed from "DOG" functions (the difference of two Gaussians), and that the visual system used a two-dimensional convolution integral with a Gaussian prefilter as an operator for bandwidth optimation on the retinal light distribution, showed that the level of mathematical sophistication as well as just brute computational power that is being devoted to sensory information processing is beyond anything we could have imagined.

Since Marr's time, there has been further progress in this area, such as the Bela Julesz's demonstrations that the visual system can extract and compute binocular disparity cues point-by-point for depth information from abstract, non-representational pictures such as random-dot stereograms. There is also the extension of Marr's ideas about monochromatic edge detection into color edge detection, the mathematical theories of nonlinear visual field distortions present in optical illusions, and many other areas.

Finally, consciousness itself may yield to research on the brain. In the last few years, consciousness has been shown to be composed of many different separate mechanisms in the brain that are being coordinated in time in order for consciousness to occur. It isn't a single process or central program that runs in the brain, nor is there a "master" brain center that one can point to where it c

I am fairly familiar with Polanyi's work and I thought it might be helpful to suggest who could benefit from this book. I would recommend this text to scientists and students who are interested in the philosophical issues and implications of their work, epistemology enthusiasts, philosophy students, and anyone trying to grapple with why Cartesian philosophy doesn't seem to explain reality.

Personal Knowledge is a dense read and Polanyi expects the reader to be familiar with many scientific and philosophic histories. It will require several reads to begin to get a grasp on the core of the material, but even a cursory reading is enjoyable and will challenge your thinking.

If you are not hip on philosophy, but are still interested in Polanyi's view of knowing reality, there are several texts available. If you don't know what the Cartesian Enlightenment is, then Meek's text "Longing to Know" is an excellent lucid primer that a high-schooler can understand. Drucilla Scott's text, "Everyman Revived" does a good job of expositing Polanyi with some biographical data as well.

The reason I rated this text 5 stars is because it is one of the best books I have ever read. However, it is not for everyone. not even a small minority of people will truly enjoy this book. So I hope I helped you become a member of the fractional minority or vice versa.

In Part I, in order to illustrate the concept of the tacit coefficient of knowledge, Polanyi uses the example of handling a hammer in order to drive in a nail. He likens the hammer to the linguistic and symbolic tools that we assimilate into our subsidiary awareness in order to reach towards that which is focal. For his word-picture, not the nail, but the entire act of driving in the nail is part of our focal awareness. As we increase in our skill of knowing, our ability to bring structural tools into subsidiary awareness increases, just as we grow less aware of the hammer's existence until it is merely a sensation against our palm. Part II contains the example of using a map or a diagram to navigate. While we can articulate the relationships between various aspects of a diagram, exactly how we assimilate it in order to find our way is beyond our ability describe. This is another tacit component of knowledge.

These illustrations are part of Polanyi's larger project: a critique of the so-called "objectivist" model of scientific knowledge. As he explains it, this model of knowing claims that human beings can, and should, have a disinterested approach to the evidence that lies entirely outside of us. The goal in this project is to determine what reality is without going beyond experience. In Part III, Polanyi describes the corollary to the objectivist model: the "tool" of doubt. The desire for purely empirical data requires that humans doubt voluntary belief, passions that are not justified by evidence. At the end of this doubting enterprise, which Polanyi maintains cannot be carried out consistently, lies modern skepticism.

In opposition to this objectivist doubt, the Polanyian model requires the personal involvement of the knower in order to make commitments to knowing, fueled by a passionate interest in a pattern which they sense corresponds to reality. Thus, Polanyi claims, true knowing bridges the disjunction between the objective and the subjective. One way in which he demonstrates the futility of withdrawing personal participation in knowing is the example of the "logical inference machine" (258-9). He says it is "logically absurd" to say that a logical inference machine "draws inferences of its own" because we must ultimately accredit its conclusions as our own. Here he demonstrates that formalization--something which the objectivist model leans upon heavily--can reduce the tacit coefficient to "obvious informal operations" but can never truly eliminate our personal participation. Thus, the machine of the scientific process is never truly autonomous but requires knowers to accredit it. His analysis of the lingual aspect of knowing is subtle and impressive, especially in illustrating the way we use language as a tool. Any critique of his model would necessarily contain formalized logical inferences but yet require those very tacit elements that he has defined. Thus, it seems that once the reader is convinced of, or even brought into a preliminary acceptance of his model, it becomes nearly impossible to refute.

Polanyi's highly convincing model does not come from a Christian commitment, and as his own writing would imply, this has a tremendous impact on how he reasons. While I doubt that we can draw a systematic "biblical epistemology" out of the Bible, there are elements of scripture that dovetail neatly with Polanyi's assertions. Psalm 63 is a good example of the passion involved in knowing. The Psalmist "thirsts" for God and as he meditates on Yahweh (most likely through the language of scripture) he is "satisfied as with fat and rich food." John 6:27 uses food as a metaphor for knowing God as well, specifically through the bread that the Son of Man gives. The book of James gives insight into how knowing God occurs within the context of commitment and submission to authority. Can we know something without entering into a commitment to knowing? The proposition that "God is one" is known by