BULLETIN OF MATHEMATICAL BIOPHYSICS

VOLUME 11, 1949

BOOK R E V I E W

NORBERT WIENES,. Cb~b~r~e~cs or C,o~rel a n d . C ~ l ~ t u n b ~ , t i ~ TJ~ A~imal and Th~ Maah/~ . 1948. 194 pp. New York: John Wiley & So~ , Ine. ~Paris: Her-

m a n n et Cie.

Cybernetics is the name coined by Professor W i e n e r and I r i s frlend, Dr . Ar tu o Rosenblueth, for the set of problems centering about commumcation, control and statistlcal mechamcs" (p. 19) and .the present " p r e i h ~ . a r y book" (p. 153~) gives the fundamental concepts on which this branch of mathematics is based as well as a brief survey of the fields to which i t might ~be applied�9

The introduction of about 30 pages relates in detail how cybernetics grew up. I t tells how Wiener, Bigelow and Rosenblueth came to pttblish tlieir classi- cal paper, of the Princeton meeting of physicists and physiologists, how, then, the Macy Foundation made possible regular meetings :in which:the'~Princeton group was enlarged by psychologists, sociologists and anthropologists~ as well as ~by neuroanatomists and neurophysiologists.: I t tells how the a ~ b r was re- quested to write the present book, and it hints finally at the sociological conse- quences when more and more controls will be bui l t by a p p l i e d c y b ~ c s which ~re "bound to devalue thehuman brain at least in :its ~ p l e r and:~aore rout ine decisions" (p. 37).

The word "Cybernetics" is derived from the Greek , p ~ e~p ~ ~ v 7 a the lat in gubernator. The present reviewer regrets the rendering o f t he Greek "K" , the Lat in "G" by a "C". He would have preferred another K. Of ~ couvse, there are cathodes, but a patient suffers from a kyphosis!

The first four chapters of the book explain on 96 pages the t h e o r y . I t be- gins easily enough, with a charming quotation from Wilhelm 'H~y:-(d~ :[554) :

"Weisst Du wieviel Sternlein stehen An dem blauen Himmelszelt? Weisst Du wieviel Wolken gehen Weithin fiber alle :Welt? Gott der Herr hat sie geziihlet Dass ibm auch nicht eines fehlet An der ganzen grossen Zahl."

This leads easily to the recognition that the meteorologist deals/'with a v a s t number of approximately equal particles, closely coupled together,' : while t h e astronomer studies a relatively small number of particles, gTeatly diverse in size but coupled with one another only in a very loose way. T h e :~ lS~er goes on to discuss the direction of time, evolution, automatons and rdl~ot.w the ages, all in a simple language which even a biologist can Understgndi

The steep ascent to the pinnacle of mathematics i s unde~ke~n~i~ the "next chapters. The second one, .start ing out from Gibbs' statlstmal mechamcs ~nd Lebesgue's theory of measure shows "how the Whole theory of' m~a~re*preserv- ing transformation can be reduced to the theory of erg~lie ~ ~ f ~ r m a t i o n . , ' The third chapter defines information on the premise that , i i i f0~ t1~on i s : t he

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146 BOOK REVIEW

recording of a choice between two equally probable simple al ternat ives." The amount of information can be defined as " the negative logar i thm of a quant i ty which we may consider a probabil i ty" and "is essential ly a negative entropy" (p. 78). The theory of t ime series, information and prediction is then developed a t some length. The four th chapter concerns i tself with the theory of feed-back mechanisms, their role in control of performance, and the consequences of thei r breaking down into oscillations.

The res t of the book shows how cyberne t i c s is applicable to biology and ~ciology. ~omput ing :machines and the Nervous System~ Gestal t and Universals , psychopathology and, finally, language and society are examined from a cyber- netieal point of view. Throughout i t is stressed tha t the important problems a re not those of energy or of ma t te r but those of order, i.e., of information. "The mechanical bra i~ does not secrete thought as the l iver does bile as the ear l ie r mater ia l i s t s claimed, nor does i t put i t out in the form of energy, as the muscle pu t s out i ts activity. Informat ion is information, not ma t te r or energy. No ma te r i a l i smwhich does not admit this can survive a t the present day."

This t ru th may by now be self-evident to many, i f not .to all, who actively work on problems concerning the brain, and is implicit in the whole work of Rashevsky and his school as the numerous diagrams of neuronal circuits which they have constructed show. But the tendency to chase "nervous energy," "Sin- nesenergie" through the labyr inths of cerebral pa thways is perhaps stil l lin- ger ing on among epistemologists and their friends. Wiener 's book can be ex- pected to c lar i fy definitely our thoughts.

Space does. not permit to discuss the las t chapters in detail. There is much food for thought in them, and there a re passages with which many readers will disagree. Let them s ta te their objections as clearly as Wiener s tated his case, and they will have benefitted by their reading!

Being a neurologist the reviewer is na tu ra l ly inclined to evaluate the book peering out of his own l i t t le corner as i t were. He der ives some encouragement for his provincialism from his associations with Professor Wiener in the "Macy meetings" ~rqm which he carr ied with him the impression tha t the author, too, is passionately interested in the bra in and i ts working. The outline of a theo- ret ical neurology is there, but i t is still so general as to require undoubtedly much fur ther work before i t will give us full insight into neurological problems. Such work has indeed been actively pursued by Wiener and Rosenblueth, and has even pa r t l y been .published. Control of muscular act ivi ty by the bra in is evi- dent ly achieved in different ways. The control of voluntary movement, which Wiener considers (see, especially p. 113) is achieved by a system of several feed- backs. The control of respirat ion, on the other hand, which Wyss and his col- laborators ana lyzed so br i l l iant ly is obviously based on frequency filters in the sol i tary t ract . Hence, one may be well advised not to ta lk too glibly about " feed- backs."

How ad~luate Wiener ' s definition of information will prove to be, only the fu tu re c a n tell. T o define information as a simple choice between two al terna- t ives should evoke some contradictions from the Gestal t psychologists. How fa r or when tha t symboiific function which was emphasized by Craik ("thought m~le ls rea l i ty" ) and which is increasingly commanding attention in cer tain quarters , can be handled by Wiener 's theory, is another puzzling question.

I t is not the least value of a good book to set the reader thinking beyond the actual c o n ~ n t s of its pr inted pages. The preceding .paragraphs intend first of al l to show tha t Wiener did wr i te a good book. In fact , any one who is or should

GERHARDT VON BONIN 147

be interested in problems of relations, be they of neurons or of human beings, or of any other units, or in problems of information, linguistic or othexwise, can do no better than to read faithfully not only Wiener but also all the references he gives!

Unfortunately the publisher has done less than justice to the book. There are several misprints which any good proofreader should have caught. Thus on page 69 in formula 2.24 there appears "].i.m.," while formula 2.25 has correctly "lira." On page 77, line 8 reads "note tha t is of the form and." Obviously ,two formulae have dropped out. The lack of an index in a book which touches on so many subjects i s also regrettable. But it should be stated in all fairness tha t ,the book is printed on quite heavy paper and seems to stand handling very well, hence it can be leafed through time and time again to find a lost fact or name.

To have made Kybernetics (~/r explicit and to have delineated its scope and its methods is Norbert Wiener's great achievement.

GERHARDT YON BONIN Department of Anatomy Universi ty of Illinois

L I T E R A T U R E

Craik, K. J. W. 1943. The Nature of Explanation. Cambridge: At the Univer- sity Press.

Wyss, O. A. N. 1943. "La l~gula t ion de l'Activit~ Respiratoire Motrice." Jou~'. Suissr De Medicine, 73, 961.