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Product: Book - Hardcover
Title: On Intelligence
Publisher: Times Books
Authors: Jeff Hawkins, Sandra Blakeslee
Rating: 5/5
Customer opinion - 5 stars out of 5
Loved the book, holes in the theory

This is one of the few books to posit a theory of human and general intelligence, and the only book of the few that is clear and well written. I think it is seminal will re-ignite interest and activity in building intelligent machines. A pleasant interesting read even for those not working in the field.

In one sense, this is a side issue since one can probably build intelligent cars, vacuum cleaners and search agents without consciousness, but in another sense it's a crucial aspect of our experience. Hawkins claims that consciousness is just what it "feels" like to have a cortex. I differ. My guess builds precisely on Hawkins suggestion that the cortex is a generative (my word, his is associative completion) hierarchy. That is, we synthesize/simulate the external world inside our head. But, we're a social creature and place a lot of value, evolutionary and otherwise on being able to imagine/simulate the mental state of other people ("my boss will be angry if I do that", "she likes me", ...). Yet, as a mater of simple functioning, we must also simulate ourselves in the world to know how to act. In my mental world, I simulate myself when I consider whether I can squeeze through a gate or lift a weight. When our simulation of mental state became grafted to our simulation of self, I think consciousness came about as an epiphenomena - consciousness is our simulation of our selves, of our own internal state.

Some holes which might exist either in my brain or in Jeff Hawkin's theory:

P-173 Attention gets pretty short shrift in the presented theory down to an alternative, hierarchy bypassing pathway in the Thalamus that gets turned on by higher regions if unexpected events occur bellow or the higher region is directed externally - the last is somewhat circular reasoning: attention is turned on if attention is directed. John Reynolds at Salk has been studying visual attention in monkeys and is finding evidence of boosting or diminution of contrast is what visual attention is doing so that visual items win or loose the inhibitory competition between features and that this is perhaps what lets some items rise up to conscious notice.

Attention is fairly sequential and substantially bottlenecked for what it can process (see "change blindness" illusions http://viscog.beckman.uiuc.edu/djs_lab/demos.html ). In many of these illusions, you don't notice when huge portions of the visual scene change, items appear or disappear etc.

Hebian learning is great, except that it also unlearns equally well. I quote Grossberg's term for the problem in caps above. Memory needs some kind of gating mechanism or it will rapidly turn into mud. Either memory is unidirectional (connections start out high and only shrink, or starts out low and only grows), and/or there is a gating mechanism that isn't well explained here. What stabilizes learning? P-136: a purple "bucket" became "indigo" (or a page earlier, orange is placed in "red"). First of all, this can shoot down a whole painstakingly learned hierarchy of learning above - in general, a bad move. Ever done visual tracking algorithms? - if you allow your template to adapt a little bit in say tracking a face, pretty soon a little bit of background "wall" starts entering the template and pretty soon "wall" becomes your (very stable) "face" template. The same thing will happen here - color buckets will randomly turn into each other, drift around - chaos. Just like our legal system, most new rulings should have very local effects and only very rarely will something ripple changes through the larger system. If this happens too often, the whole structure collapses.

Finally, this ignores all the critical period stuff in learning. Some things are laid down early and in clear order and they don't seem to change and if not learned early just cannot be learned. Famous study of this is "Kitten in the carousal" where kittens are raised in the dark and only get to walk in the light in short intervals where one cat can move but is mechanically yoked to another cat who sees the exact same things, but is stuck in a carousal (a little box) so that it's leg movements don't control it's movements. If this is done too long, the poor kitten in the carousal never learns to see (depth) at all! Even when let go into the light. If let go early enough, it will learn to see normally.

Long winded, but: Seems to me that some basic categories and features must be developed early and not allowed to change in order to have any chance of building a larger structure over them.

Where did it go? I see sequences, but not timing - you can't control your muscles without actual timing, not just sequence. In fact, time itself is yet another unstated sense. There are clearly integration rates that are learned and used in recognition, planning decisions etc.

I still don't get exactly how invariance is found by this architecture beyond things that can be predicted which is somewhat of a tautology - yes, invariant features make your life easy, but beyond dumb luck, how do you find them? When you identify a dirt road by parallel tracks in the soil, what inside you is discovering the cross ratio projective invariance? How did we learn brightness normalization? Color constancy? Some of this stuff involves tricks in active diffusion of color information from edges and clever local integration. Is this learned or built in? Insects must have to deal with this and must be born with it. How do they do it?

P-158: Thinking of doing becomes doing. Yes, but how to you stop this from happening? Indeed, how do you start one invariant representation of say the Gettysburg Address from being spoken, written by all limbs and done in interpretive dance once you think to do it?

Minor nits:
P-71 While I believe that the fundamental unit of processing is a kind of sequential associative memory, the fact that you think or recall serially doesn't prove this - perhaps you can recall everything in you house at once, but internal or external output is one thing at a time and nearby things just have a scotch more support.. Detailed motor execution is more compelling.

I could have done with a final summary 2 side to side page cortical sheet diagram with Thalamus, Hippocampus, and at least 2 layers of hierarchy with all the basic communication channels and their direction shown, even better with text referencing where these things were described.


Product: Book - Paperback
Title: Apple Confidential 2.0: The Definitive History of the World's Most Colorful Company
Publisher: No Starch Press
Authors: Owen Linzmayer, Owen W. Linzmayer
Rating: 2/5
Customer opinion - 2 stars out of 5
A disappointing overview of Apple history

Although packed with funny anecdotes and small, nice-to-know facts, overall this is a disappointing read. The chapters are hardly related to each other, it is definitely not usable as a historical/chronological overview of the company and most of the one-liners in the margin are undated. Therefore it is often not clear to which period or subject the text is related. It makes that this book leaves a very fragmented impression. Pity.

Product: Book - Paperback
Title: Designing Web Usability : The Practice of Simplicity
Publisher: New Riders Press
Authors: Jakob Nielsen
Rating: 5/5
Customer opinion - 5 stars out of 5
Good Book

Good book, with common sense advice. I think every Web Designer (especially beginner ones) needs to read this book. However it is wordy, and much of the information focuses on what is wrong with a particular web page. It doesn't always focus enough on what can be done to fix the page. Overall though, this books positives far outweigh any shortcomings.

Product: Book - Hardcover
Title: Microlithography Science and Technology
Publisher: Marcel Dekker
Rating: 5/5
Customer opinion - 5 stars out of 5
E-beam Lithography

The book provides a great overview of the Electron Beam Lithography, which was the material of interest for me. Material is conveyed in great detail while the meaning of the material is not necessarily constricted to the experts. As an undergraduate student, I found the material readable. I was also able to understand most of the information well and as a result I believe I have a good base of knowledge about lithography. I would definitely recommend this book to other students.