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Catalog of Chromosome Aberrations in Cancer (4th edition)Felix Mitelman (ed.). John Wiley & Sons, Chichester. Pp. 2,056. Price £160.00, hardback (two volumes). ISBN: 0 471 56087 1.

For nearly two centuries past, the praise of experimental enquiry in the cultivation of the sciences has been a common-place theme ; and it must be allowed, that the advancement of physical knowledge during that period, has been chiefly owing to the great extent to which researches of this kind have been pursued. There seems, however, to be now reason for apprehension that the progress of science is as much retarded by-the want of sufficient reasoning on known facts, as it was in more ancient times by the comparative neglect of observation, and an undue bias for purely mental speculation. It is much easier to observe sensible phenomena and to make experiments, than it is to reason well on what we thus observe; and hence has arisen much of the fanatical admiration for the prevalent notions on this subject: for it is by such proceedings that many men have been enabled to make a figure amongst mankind, that otherwise would never have emerged from utter obscurity. The authority of Bacon has been commonly adduced in support of those notions ; but it is probable that, had Bacon lived in the present era, he would have considerably modified his precepts for the advancement of knowledge, and have attributed more importance to those efforts directed towards the generalization of the facts which have been collected since his time, and which are comparatively useless, because they have not been sufficiently reflected on. But the error which has caused the greatest waste of human industry, is that 'which has supposed that theoretical principles are not necessary in order to prosecute experiments with the probability of useful results; and, because some important discoveries have been arrived at by experiments made at hazard, a multitude of men have entered blindly on such enquiries, who have been unable to reason correctly even on what they may have observed. Hence the Kost of useless experiments, trivial observations, false inferences, loose analogies, and opinions without arguments tor t em? which encumber the modern records of science. The w?r fore us is written more according to the manner o p^ i oso phizing in greatest estimation amongst the ancients. it is purelv speculative. But the author does not mean to epre ciate the utility of experimental enquiry: his object is to raise the former mode of philosophizing to its proper spheie, a same time that he indicates new routes by which the lat erequiries may be extended with a probability of arriving at precise and important acquisitions in physiological knowle ge* Before we enter into a particular examination of this pro uction, we solicit the most earnest attention of the reader, or W6 have to consider dissertations comprising reasonings o no or 1nary depth, with original views which have been deveope only by the most acute penetration ; and we promise to ma e a display of what will amply reward the attention we require. ^ rru~ -e .1 ? ? 1 --.w uurj\.^(. vji tins wuru lb nil analysis ui uiose imnuic iciations in the organic life of man, "which result from the union of the properties appertaining to three departments,-?those of mechanism and of chemistry, with, those which distinguish the living from the dead state. The phenomena which are to be assigned to the properties of each of those departments, respectively, are investigated; and arrangements and classifications of them are attempted, as far as analytical enquiry has succeeded in developing the subject. After having considered in this manner the knowledge already acquired, the author, states the routes which inferential reasoning appears to indicate as best qualified to iead to further important discoveries.
Here a new region lay open before him, and, on entering it^ he appears to feel that he is travelling over untried ground;-and therefore he professes to give on the several topics of his subject indications only, which do not assume the character of perfect or positive information, but aspire rather to suggest the proceedings by which such information is to be attained ill the progress of research. T<U_ , . jLuii >vuiK oeing, then, both ot an analytical and inferential nature, the author has thought it right to commence with his peculiar doctrines of truth and Causation ; as he thus gives a precise view of the principles which regulate his subsequent reasonings, and the bases on which his propositions are logically founded. These doctrines, with the application of them to the universal scheme of nature, occupy the first of the three books into which the work is divided.
The first chapter commences with an enquiry into the general nature of truth ; and the author, by his reasonings and illustrations,.attempts to prove that belief and truth ar6 synonymous-. SS Critical Analysis, We gain the belief of an existence, he observes, either by the immediate operation of an external object upon our senses, or by a process of our own minds. An external, in relation with our faculties, produces consciousness, or a belief of the existence of such external; in other words, it is true: and no other testimony can be cited for the existence of an external, than a consciousness or conviction of the reality of the existence of such external. Thus, if it be asked why it is true that the sun or a tree exists, the answer is, " because I see itwhich means, that I am conscious of its existence, or I believe that it exists.
But it is found that the same object may produce a different consciousness, or conviction, in different individuals; as, if a sense be disordered, or the brain disturbed, real objects might assume extraordinary shapes, colours, and characters; or spectra might be perceived in an atmosphere which otherwise appears unoccupied. In such cases, the conviction, or consciousness, is as unequivocal as on points of belief which are universally received; yet the existence of these distorted objects, or of these spectra, is not regarded as true. A madman, too, has just the same testimony for the reality of his perceptions as one whose understanding is sound, namely, belief, or conviction.
The same object, then, will produce a different consciousness in the same person at different times, as well as in different persons, by operating on a different state of the faculties. Here the evidence, as far as it respects truth or reality, is the same in every case. All consciousness, then, and therefore all truth, is relative.
Truth, or conviction, is identified by the relation which the properties of an external have with certain faculties: if the external be modified, the conviction with respect to it is modified; if the faculties of perception are modified, the external remaining the same, the conviction with respect to it also suffers a corresponding modification.
It is however agreed amongst mankind, that the only consciousness which shall be admitted as truth, is that which is produced by the operation of external objects upon such a state or predisposition of the senses as is general, though not universal. Hence the author arrives at a division of truths into those which are natural, and those which may be said to be artificial: the former are, in every instance, synonymous with belief, because there belongs to them only one common testimony; that is, consciousness, belief, or conviction. The latter are agreeable with an artificial standard, which is founded on the consent of mankind; and, according to this standard, the convictions of an impaired sense or of a disturbed understanding are rejected, not because, in nature, these convictions do not equally esta-Mr. Pring's Indications relating to the Organic Life. blish truth, but because, from differences of constitution, they are not agreeable with the convictions which are entertained by the greatest part of mankind.
The author is then led to consider the nature of evidence, the grades of which are conformable with tlie degrees of belief which the different kinds of evidence produce. Evidence may be divided into two distinct species, perceptive and inferential .*? the former is experience, or results directly from an impression upon the senses; the latter does not arise from a present impression upon the senses, but is founded on analogy: thus, from a perceptible similitude in some respects, we inter a similitude in all, from our previous experience that those objects of the inference which are not seen, are in connexion with those which are seen, and the inference is justified in proportion to our experience of the frequency of the connexion.
Belief, produced by an impression on the senses, is but rarely superseded by a different belief with respect to the same object, and differs in this respect from the belief acquired by a process of the mind, from the relations of the senses with the external world being more uniform, and less complicated, than those of the understanding. But, in sensible matters, we are apt to believe more than the senses inform us of; and, in consequence of such belief passing under the authority of sensible evidence, the infallibility of the senses has been brought into question. Thus, a man who for the first time should see a shadowy representation of men on horseback, (like those produced by the?/j(7g7c lantern,) would believe them (his judgment not being otherwise instructed) to be men and horses of flesh and blood ; and he would fancy that he believed no more than what his senses informed him of.
The author obviates such objections to his general principles as those above proposed, and illustrates his doctrines by various convincing arguments. He then gives a summary of the principles of the different grades of evidence, according to the force with which they produce either unequivocal conviction, or belief mixed with doubt.
-* " 2d. Proof; or that founded on analogy, to which we know of no exception. These two are almost equal in their degree, and gene, rally produce unequivocal belief: the " 3d, may therefore be called probable evidence; as when the analogy is rarely excepted again: thus designating this class of inferential evidence by the term which has been employed to designate the whole species. . '.-'J *' 4th. Indicative evidence ; as when the association inferred ,is, more frequent from the absence of such association.
5th. The evidence of possibility ; when the connexion is knpwft Sometimes to occur. 40, Critical Analysis. " These three last, which may be considered as different grade* of presumptive evidence, give rise to the diversities of opinion ; for, as facts are pre-supposed to be in opposition, so their comparison will be attended with a different result, according as one or the other set of facts is recollected." We now arrive at the chapter on causation, in which the author develops those principles concerning the relations of causes and effects, the application of which is subsequently continued through every section and page of the wqrlc.
He commences by a demonstration of the well-known axiom, ex nikilo nihil jit; and he deduces the truth of this axiom in conformity with the rules of reasoning which are previously laid down. Having assumed that this axiom is proved, the first inference which he makes to follow from it is, that there are no elementary substances or properties, or that every possible form of existence must necessarily be compounded of other forms; for, if a cause could produce an effect which is different from itself, that in which the difference consists, if superadded to the cause, must originate from non-entity; which is contrary to the axiom ex nihiio, &c.: if the effect be only a part of a cause, some properties having been abstracted, then there is no act of production ; for that only remains, and is the effect, which was before produced. Thus, he states, " a single cause is no agent: it is a form of existence, but is capable of no transaction ; for a thing cannot supply or confer that which it does not possess: it can supply only itself, or its own identity.'' The manner, therefore, in which a cause produces an effect, is described as involving no mystery : a cause is itself, and no more than itself, and it can do no more than exist: it may exist separately as an effect, depending only upon its own constituents; but "when it, in turn, becomes a cause, and produces an effect, it is by combining with something else, and the effect is merely the union of the different forms of existence which are called causes.
Thus, an effect is identified with all its causes: it is the existence of its causes ; and the mode of the dependance of effects upon their causes is illustrated by numerous combinations, as two and two make four, because the united existence of two and two is the existence of four ; and an acid and an ajkali are the causes of a neutral salt, or produce a neutral salt, for the reason that a neutral salt is the united existence pf an acid and an alkali; and an effect appears different from its causes, because two forms of existence, when combined, have a different perceptive relation with our faculties from that which is entertained by the same forms of existence in-their separate' states. The author illustrates these doctrines by adducing numerous examples to which they apply ; but we must pass over' them, for our limits will not permit us to enter into any parti-Mr. Pring's Indications relating to the Organic Life. 41 culars on this subject. He encounters all the objections that might be adduced to his doctrine, at least, we can imagine none that he has not anticipated ; enters full)7 into the consideration of them; and, finally, shews that the alledged difficulties are perfectly in agreement with his views.
The efficiency of those which are termed remote causes, are afterwards treated of, and some difficulties belonging tq them reconciled with the previous conclusions. The difficulty which, on first sight, appears the greatest, results from our not distinguishing, in what are considered as causes, those qualities which really act as causes,from those which have no relation to the effect. We must enter into some particulars on this point, in order to elucidate it; and we take an example given by the author for the purpose : If a steeple should fall in consequence of being struck by lightning, and a man, passing by at the time, should , be killed by a stone falling on his head, it might be said, would not the lightning be the cause of the death of the man ? and, if so, how is it that the lightning, according to the author s doctrine, converts a living principle into the condition of death^.
Did the lightning exist in the stone, pass from it into the man s brain when it fractured his skull, and mingle with the living 42 Critical Analysis.
Here we must trace a process of causation ; and, though an example more palpably opposed to our doctrine will not readily be devised, we shall still find that our principle is untouched by it.
" The vital organs of the man, his animal powers, his mechanic knowledge, his facility in the art, all concur to produce one effect, which is the exertion of that ability which is produced by this complicated causation ; this effect, in its turn, becomes a cause, by which the parts of the watch are adapted to each other; the intelligence of the artificer is related with volition, or produces and modifies volition ; volition is related with the muscles of the arms and fingers; and modified motion, (motion modified according to the volition,) is the result; by this motion the parts of the watch are prepared and adapted. So that it is not a man with which a watch holds a relation as with a cause, but with a certain moving power, which is the first cause, proceeding from the man, which is exerted upon the works of the watch. If we would know whether this power of motion, or its properties, communicated to the works of the watch, still exist in them, we can scarcely answer this question, without a better understanding of the relations Qf moving powers in general. The power of motion appears to be expended in the act to which it gives rise. And, whether it enters into the substance moved, or whether it is communicated from the subject moved to the surrounding medium, in the course of its progression, is a point which in this place it is superfluous to discuss. The watch being thus produced, is then identified as an effect by its own constituents, arid is maintained by relations subsisting between its parts. The powers which concurred to produce it are its remote causes, and these may be withdrawn, or cease, while the watch preserves its identity: its real, true, or efficient causes, are those by which its identity is preserved, when its connexion with the remote or concurring agents has ceased; and these causes cannot well have a place in England, ?while the watch is at Calcutta. All this is very obvious, and requires no more to be said about it." Many apparent difficulties arise from succession of phenomena being confounded with cause and effect; all which the author takes into consideration, and he endeavours to give to the evidence of succession its true distinctions and importance. The whole object of this chapter, as far as it respects science, is, by defining the laws and modes of causation, to conduct enquirers, to deeper objects of investigation than have usually occupied their regards, and to inculcate a sort of analytical enquiry, which is required for a satisfactory understanding even of the most simple subjects.
The third chapter is an application of the preceding doctrines of causation to the general phenomena of nature. This chapter is entitled " Universal Scheme in connection with the foregoing Principles." According to these principles, the author examines the subject of creation, or origin of forms, and treats copiously of the government by which natural processes are a predisposition to another: death itself, which is only a modification of life, becomes a source of life, alternately furnishing elementary properties to the higher, the lower, and the more complicated forms ; and then mingling with, and assisting in^ the formation of those belonging to the most simple and the lowest classes. It is probable, then, he thinks, that, at a remote period of the world, the constituents in it from which the organic spirit of man would result as an effect, were disposed to unite and produce, as a separate combination in nature, the spirit in question. The concurrence of constituents at this period must have been determined by one of two modes of causation, or by both, namely, the constituents previously disguised in another constitution, were suffered to form the identical spirit by an agency which detached them from their former alliances; or by an agency which furnished additional properties to constituents which were not otherwise identical. These agree with the only possible modes of causation, by subtraction or by addition of properties, or both.
We now arrive at the third book, which treats of " Post-fetal Life," and is divided into five sections ; the first of which commences with some considerations, of a general nature, on the " condition of the spirit,"?a term which the author adopts to express those properties whose existence is inferred from their effects, and which are thus contra-distinguished to the visible structures and products. The existence of this principle, that is to say, the above properties collectively, being inferred from its effects, the next object is to class those effects, and give corresponding denominations to the properties of the principle by which these effects are accomplished. But, as the author makes it appear, the progress in this analysis and classification is not to be boasted of: " the most that has been done," he says, c< is to designate three or four species of contractility, from which has originated a vast deal of erroneous and absurd reasoning and he shows the inadequacy of all the doctrines founded on the degrees of excitement, contractility, &c. to explain the phenomena in which properties of life are engaged. But, as we shall hereafter have occasion to return to those several points in a particular manner, we pass on now to the next chapter, which is on " the mode in which life is maintained." This comprises a multitude of considerations of the most interesting kind.
The author, by his arguments and illustrations, shows that life is not to be conferred on the body by the only externals which support it, namely, by food and by air ; but that life itself, that is, the organic spirit, must operate upon air and food to the end of its own perpetuation. The following para* graph comprises the sum of his doctrine on this point; Mr. P ring's Indications relating to, the Organic Life. 47 f* The principle of life, or, as we have hitherto expressed it,the*? organic spirit, exists in every part of the textures. Blood, containing the elements of life, which are furnished by its two sources befora named, viz. air and food, is everywhere diflused among the textures. The exposure of that which contains the elements of life, to life itself^ is in this way complete. The next operation is simply this, that life, by an affinity subsisting between itself and its elements, separates them from a common material, and unites them." This act is described as being perpetual: life is 110 sooner formed than it vanishes, or changes its form, or dies; and the principle would become extinct, but that it re-produces its resemblance in uninterrupted succession from its elements, which are contained in arterial blood ; which fluid is, in the words of the author, " a further preparation of the informal life which, exists in earth and air." Thus, there is no permanent quantum of life, but it produces itself from its elements, as fire does itself from combustible substances, and lasts no longer than it is capable of perpetuating its resemblance by its affinity with successive quantities of its elements, which are derived from earth and air. All the properties of life, those which are passive, as well as those which are active, are renewed in this way; and this is described as The following are some of the author's conclusions on this subject, which are here adduced because they are of a general character. il I. The quantum of the spirit depends upon the quantum of the elements exposed to it, which are contained in the blood.
ii 2. The quantum of the elements depends upon the preparatory functions.
" 3. The disposition of the spirit, in regard to the structures, is regulated by latent causes which belong to it. " 4. The quantum of the textures depends, 1st, upon the quantum of the disposed spirit, and, 2nd, upon the quantum of the organic particles in the material. " 5. The quantum of the organic particles in the material, depends also upon the function of the preparatory organs." Another point of view in which the subject of growth is discussed, is with respect to the absorbent function. Here we must fairly confess our inability to give any thing like even hints of the author's propositions, they are so multitudinous, and all so intimately connected; at the same time that we acknowledge the very great degree of interest attached to his numerous original indications. The whole of this chapter hears very close indeed, on the practice of medicine ; but, as we shall hereafter find others that stili more intimately relate to it, we Mr. Pring's Judications relating to the Organic Life. 49 must proceed to the next in order, which is on "animal heat." The discussion on this subject, too, will not admit of abiidgment; but we may state, that, after showing that there can be no source of heat in any one organ or structure, he thus explain^ the formation of animal heat. It is proved, by the influence.or. heat in incubation, that it is necessary to identify the living principle of such animals as possess it; it continues in anima, s as long as life lasts, and helps to constitute, or is a part of, the principle of life. This principle renews itself by assimilation from arterial blood, which contains all the properties ot life, and those of heat in an informal or elementary state. 1 hus, as a principle assimilates, or renovates itself from its elements, heat, as a part of that principle, is, in the same way, and at the same time, produced. The arguments for this doctrine, together with the objections or difficulties which suggest themselves with respect to it, are stated and discussed.
In the fifth chapter the author analyzes the relations subsisting between vital, chemical, and mechanical agents. The relations of these departments with respect to each other are traced ; and it is attempted to assign the respective shares, influences, and co-operations of the properties belonging to these classes in the phenomena in which they are mutually engaged, and which comprehend every possible process or agency which can occur in an animal body. in tiie next chapter, the relations of the properties of life "with each other in different seats are considered. Many points of abstruse research are here entered into in the analytical way ; an application of the doctrines of causation being here made, and the investigation conducted upon the views which these doctrines suggest.
1 he evidence which is afforded by the ordinary methods ot experimenting, and particularly upon the nervous system, is minutely scrutinized and defined ; and exposition made of, the fallacious reasonings by which conclusions in physiology have been deduced from experiments made without any precise views, and conducted in a loose manner.
The relation of vital properties in one with those in another seat, are stated to be, 1st, direct; and, 2d, indirect: direct, as when, the properties being affected in one seat, the influence ol this affection is communicated to those in another seat, without any change in the alliances of the latter, whether chemical or mechanical; indirect, as when the function of an organ whose office it is to prepare the chemical for the use of the vital properties in other seats, becomes impaired, in consequence of which those properties are elsewhere affected, by a disturbance ot the relation which subsists between them and the chemical or other, *0.257. " h * -50 Critical Analysis, products of the organ, and not with vital properties belonging to the organ. The more evident examples of the latter are furnished in the preparatory organs, as the stomach, &c. The above relations, as well as the properties of life belonging to particular seats, are finally arranged under the following classes: 1st. Assimilating properties; 2d, regular dependant, and, 3d, occasional properties of life. The first is the organic life of every seat which renews itself by assimilation, and is dependant for its renewal only upon its own existence, and the supply of arterial blood. The second class (the regular dependant properties of a seat), refers generally to that functional life of organs which is identified by receiving the properties of a distant seat.
This class of properties is indicated, by experiment, ih some functions of organic life, as in those of some of the secretions, and is illustrated with less ambiguity in the dependance which the muscles of respiration acknowledge on a communication with a centre of nerves. The third class (or the occasional vital properties of a seat), includes all those instances in which properties of one seat are made, by an occasional cause, to influence those of another, between which there was no habitual dependance, no reciprocation of function ; as when the action of the heart, or the function of the brain, is disturbed by infliction of an injury in an extremity, or by a disturbance of the natural relations and spheres of spiritual properties. This class relates chiefly to disease or preternatural condition . The two last classes do not maintain themselves by assimilation in the secondary, or communicated, seats ; for they would live independantly of a communication with their sources, acknowledging, like the first, a dependance only upon arterial blood. This division is a leading one throughout the subsequent sections. It is not right to praise any particular part of this work; but we have deeply felt this restriction on the expression of our sentiments at the conclusion of the consideration of this chapter, as well as of several others that we have already passed. The chief design of the chapter we are taking leave of appears to be, to inculcate that strict analytical enquiry which the author has sketched in his preliminary disquisitions, and to show the applicability of his principles to the general objects of scientific investigation.
The second section of this book treats of the preparatory organs of the nutrient materials; and the first chapter contains a more minute or extended view of the previously considered relations of life, and of the modes of enquiry which are adapted to their elucidation. From general views the author descends to more particular investigations ; and the second chapter, on the stomach, commences his indications for an analysis of particular functions. The following is the leading divisions of the Mr. Pring's Indications relating to the Organic Life. 51 topics of this chapter. The relation subsisting between food and the function of the stomach is to be considered (contorniably with the general division before expressed), " 1st. According to the mechanical relation subsisting between food and the structure of the stomach. " 2nd. According to the relations between the chymical constituents of food and those supplied by the stpmach.
_ > e'ti. " 3d. According to the relations between the vital properties 0 ^ e stomach and the properties of the same kind in food: thus far t ey way be considered separately. They are also to be considered reciprocally ; that is, as the stomach acts upon food, and the converse.
I hey are also to be considered as regular and occasional.^ Last y, their mutual or conjoint agencies are to be considered according to t e following order: " 1. Mechanical relation. " 2. Chemical relation. " 3. Spiritual relation." Each of which is subdivided, and the ends of the specification fully exposed. We must again state our inability to give any thing like a satisfactory abridgment of this, and of the ensuing chapters on the preparatory organs ; for every paragraph, unless employed in the examination of received opinions, contains a topic of research, or an indication for additional enquiry.
The order of investigation which the author adopts is everywhere of the analytical kind, and every inference gives rise to an original indication. We have not much space left for this article, and we are desirous to arrive at the part of the work on. the nature and origin of Disease, on Therapeutics, and on. Death.

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The third section treats of the relations of Blood, and its products, in its vessels, and in the several places of its distribution^ ?The chapters of this section are enumerated under the titles pf " the Formation of Blood," " the Lungs,1' " Arterial Blood, 'Relation of Blood with the Heart," " other Relations ot Blood," " the Absorbents," " Secretion," and " Relations of the Organic Life in the Nervous System." These chapters contain few or no theories, and consequently there are no doctrines to be exhibited. The enquiry is, throughout, an indication for further analyses, and the development of the subject is conducted upon rules of the closest Reasoning. The object ot */r ?uthor is here, as in the other instances, the discoveiy ot efficient causes; and his reasonings land indications Avith a view to the future attainment of this description of knowledge, ,ar^ applied to the most abstruse and nearly inscrutable processes.
Jo the last chapter of this section, on the relations of the ?rgauic life in the nervous system, the relations of the proper-52 Critical Analysis.
ties of life in tliis system are traced in the analytical way, conformably with the division of the properties of life into three classes, which has been already quoted. The chapter is occupied in considering the several relations which involve the properties respectively, and mutually, of either class. The rules of conducting experiments with a view to ascertain the relations of the nervous system are sought after and defined, and the kind and degrees of evidence specified which belong to the facts from which relations are inferred. Among other relations, that of electricity with the properties of life is considered. The author regards all the attempts to identify life and electricity as little better than puerile: he considers electricity as intimately connected with life, and capable of influencing, modifying, and even substituting, some of its properties; but, after enumerating a multitude of particulars in which life and electricity are totally different, he concludes, that the phenomena of electricity furnish no general analogy by which their identity with life can be correctly inferred. The fourth section is on the general nature of Disease; and, in the first chapter, the author makes such an inferential analysis of disease, with a view of tracing its origin, as is conformable with his doctrines of causation. He begins with a definition of health, predisposition, and disease, and states such examples of them as serve as a point of reference to the subsequent discussions into which he enters. He distinguishes disease into primary, secondary, and general; and its origin into accidental or spontaneous. " Primary, as when it originates in one seat, by a causation peculiar to the properties of this seat; secondary, as when disease is extended from the original to a related seat; general, as when, in some form, few parts of the system are exempt from it; accidental or foreign, as when disease is produced by external agents, which are related with properties common to the healthy condition of the species, as in the instances of wounds, poisons, &c.; spontaneous, as when disease happens without any external assignable cause; or as when it is excited by a natural cause, as air, food, &c. operating upon a state of constitution which does not belong to the healthy condition of the species." The author traces the origin of disease to a spiritual predisposition, or a predisposition made by latent properties of life ; and the development of disease is supposed to engage a series of changes in spiritual properties, which is commensurate with the first formation of the ovum. The manner of progressive change among constituents, by which passive spiritual properties become active, by which disease occurs, and b}r which all spontaneous successions of phenomena, and all the conversions of the structures are determined, is thus described: Mr. Pring?s Indications relating to the Organic Life. 53 " Progressive change is accomplished by reiterated causation. If a thing preserve an uniform identity, it docs so bccause it is surrounded by no agents which are so related with as to affect it; if a thing is once changed, and then preserve its new form, it is that it is exposed to the operation of a related agent, and that the form which it assumes in consequence ceases to be related with the existences which surround it; if a thing suffers one change, and then another, and a third, through a lengthened series, it is because each successive form of existence has a causative relation with other forms." The application of this doctrine of progressive change is frequently made, in aid of the subsequent investigations, and its application to the sensible properties of the body is familiarized, at the same time that it is illustrated, by a rapid sketch of the development of the moral properties. Here, as in the rest 01 this section, the author discusses the systems and opinions relative to this subject which are generally received, when he develops his own peculiar views, always connecting with his doctrines the evidences by which they are.supported.
If any part of this chapter may be considered more estimable than the rest, it is that which relates to predisposition to disease: it is an admirable example of the utility of the author's doctrine of causation in pathological reasoning, and merits the deepest meditation.
The indications we have already met with on the subject of disease, and the illustrations with which they are accompanied, disclose a multitude of things of the deepest interest and importance to the physician ; but, as the pursuit of each series of them might furnish matter for the labours of a man's life, it must be long before the good that may be expected to emanate from this work will be realized ; and we venture to prophesy, that, in this long interval, many men of mean talents will draw secretly from it, and sport their little lights, to glitter for a time amongst mankind, whilst they endeavour to obscure the name ?f Daniel Pring and his il Indications," with as much anxious care as shrewd and eminent churchmen have used to conceal the Court of the Gentiles" ot Theophilus Gale.
In the second chapter the author considers the more precise origin of disease in one seat, agreeably with the doctrines of progressive causation above expressed. This chapter is little more than an illustration of principles before laid down, and the author thus states the axioms he means to establish from the illustrations just adverted to.
1st. That every primary spontaneous disease is produced by pro? gressive change in the constituents of its scat. " 2d. That this progression may be interrupted, when the present state ceases to find a causative relation with existing causes.
" 3d. That, if the progression of change is resumed, it is bccause 54 Critical Analysis, new causes obtain a relation which did not before exist with the constituents of its seat. " 4th. That these new causes may come to produce change in a given seat, either from progressive internal change among connected properties, or from exposure to an external cause which is related with the present predisposition of the seat; these might be complicated." The difficulties in tracing the history of spontaneous disease, although the laws relating to it are so few, are by no means trifling: we take an example from amongst those the author has adduced as the subject of discussion. Say a tubercle forms in the lungs: why docs it form there ? The part, it may be said, becomes thickened by coagulable lymph, which then becomes organized, grows, suppurates imperfectly, &c. Why was the lymph thrown out? From inflammation. Why did the inflammation occur ? Excited by cold. How came the part predisposed to such a relation with cold? It has somehow attained such a state. Now my abstract refers to this word somehow; and, if this somehow is to be answered, the only reply that can be given will be found in the above propositions, which I have called axioms. To leave, then, this subject of the manner in which disease begins, and without taking any farther with us the incumbrance of these views, we will simply say, when disease occurs spontaneously without any assignable external cause, that it happens from the development or operation of latent causes, about which we have been of late so busy; and, that when disease happens from an external assignable cause which does not produce the same effect in others, or in the same individual at other times, we will say that a predisposition existed to the operation of such cause, of the nature of which predisposition also enough has been said in the way of indication." The causes of disease, then,,are of two kinds: " 1st, those which, being related with the spirit (the vital properties), have the power of affecting it, and producing disease as often as they are communicated, or as long as thejr continue to reside with the spirit; 2d, those which may modify for a time, or permanently, the identity of the spirit, even though the operation of the primary cause should have ceased. The state of the spirit produced by the first class of causes is not an assimilating one ; the state produced by the second is either maintained by assimilation,, or runs into a succession of modified states^ each capable of assimilation." The rest of this chapter is occupied in discussing the relations of the chemical and mechanical, as well as the vital, properties, to the origin of disease; and, having traced-the origin of disease to certain states of the organic spirit, or, in the common term, the vital properties, he considers, in the third chapter, " the general nature of the disease of the spirit," and especially the 1 Mr. Pritig's Indications relating to the Ofganic Life. B5 laws respecting the duration of disease. We must here also state our inability to give an abstract of the author's analytical and inferential disquisition: we can only say, that it throws a new and brilliant light on the peculiar nature, as well as on the distinction, of many acute and chronic diseases. It contains, also, some very ingenious notions respecting the causes of the insusceptibility to several diseases a second time, and the reasons why this insusceptibility is occasionally not acquired.
The fourth chapter is on " Disease of the assimilating, of the regular dependant, and of the occasional, Properties of Life. The objects of this chapter are, to show what classes of disease belong to, or interest respectively, these classes of properties.
The modes of discriminating between the affections of one class and those of another are sought after, and the intercourse and re-agencies of each.class are exhibited, with appropriate illustrations. The degrees of evidence which succession furnishes with respect to the relation of cause and effect, is here recapitulated with especial minuteness ; and the author exposes the grounds upon which true or false inferences of causation are liable to be made from this description of evidence. This chapter cannot be too deeply meditated on by the medical practitioner ; and the subsequent one, " on the general Nature of related Disease," is hardly less interesting to him.
The author divides related diseases into two classes : those in which a primary ceases upon the occurrence of a secondary disease; and those in which disease continues in a primary seat, and runs its course independantly, notwithstanding it produces consecutive diseases in other seats. The first the author designates as " a substitution of diseasethe second he denominates " related extension of disease." The author here sketches numerous examples of both classes. He considers the formation of fat as a substituted disease, and the one which, of all others, occurs the most frequently. The formation of fat, he thinks, tends to maintain health by defining a. harmless seat of disease while it lasts, and it is seldom spontaneously removed without the occurrence of a substituted disease in some less convenient seat. He gives a rapid sketch of several examples of disease of this class, and then enters, in a similar way , into the consideration of " extension of disease." After having adduced sufficient illustrations of diseases of this class, he discusses the chief of the prevalent doctrines, and shows how little many of them will bear the test of analytical examination. He enters more particularly into the refutation of those doctrines which assign, arbitrarily, one organ as a common, or universal, seat of the origin of disease. The bad reasoning of the pathologists who maintain these views, is freely exposed; and the author concludes this chapter by a citation of facts and 56 Critical Analysis. evidence which bear upon the subject, and shows, upon the credit of this evidence, what inferences are to be legitimately drawn.
His examination of the prevalent doctrines about <? metastasis" and <c conversion" of disease, relates in the most intimate manner to the practice of medicine, and may therefore be designated as the part of this chapter that will be most generally interesting. The author's whole course in this chapter is strictly analytical and inferential, and we recognize at every step the powers of reasoning that produced the disquisition on causation. We could adduce from it many striking examples of the necessity of our extending our views beyond those from "which the pathology generally received has been sketched, if we would obtain real knowledge of the nature of most diseases; but our closing limits oblige us to proceed to the chapter on Therapeutics.
The author commences with a retrospect of his doctrines of diseases, on which his therapeutics are founded, and then enters into the consideration of the application of remedies ; and his doctrines of causation are again brought into active service on this very important occasion. We can here adduce nothing but some of his more general propositions ; and first his classification of remedies, in the application and arrangement of "which he afterwards proceeds. Curative remedies, he says, may be divided into three classes : " 1st, those which cure by a direct relation with the cause of disease; 2d, those which cure by removing or obviating a perceptible (or sensible) cause of disease by an intermediate relation; Sd, those which cure by latent causation.'' These classes are respectively exemplified.
The subdivision of the third class, or remedies which operate by latent causation, are thus enumerated: 1st, those that cure without a sensible operation ; 2d, medicines that produce cure by sensible change, or by sensible effects ; 3d, medicines that cure by employment on the seats of disease, with or without sensible effects ; 4th, medicines that cure by an operation upon related seats, with or without sensible effects." This subdivision is thus exemplified : " 1st. Medicines that operate without sensible effects. In this manner arsenic may cure intermittent fever, scorbutic disease, &c. In this way diseases are cured by bark, by antimony, and,mercury, in small doses, &c. The cure in these instances is accomplished by successive causation, and, consequently, the relation of the remedy with the condition of the disease is mediate.
Thus, a disorder of the head is cured by emetics, or anasarca o o legs by purgatives ; or a disorder of the head, existing beneath t e cranium, by the actual cautery to the scalp ; or a disease of the by an issue in the arm or a seton in the back of the neck ; or as a isorder of the stomach is cured by purgatives, or an inflammation of t e pleura by blistering the skin ; or as a disease of a joint is cured by a caustic issue, &c. These remedies act also by successive causation, or by a series of related processes." The author then proceeds to connect the doctrines which he has formed on this subject with those pathological principles before laid down,-after the following manner: Mr. P ring's Indications relating to the Organic L\fc. 61 The concluding section is on <c the Death ol the Qiganic Life;" and the author, in the first chapter, considers '* death in connexion with disease." Death, lie says, happens either, " first, trom defect or modification of those causes which maintain life, and which have been sketched in our physiology ; '2c, from the operation of certain related external?. ' The history of death begins with the history of disease. 1 he origin of the spontaneous processes which terminate in death, is in the Mtal properties; but death may take place either, " ist, from pvimar)7j or, 2d, from secondary disease." These modes are then elaborately discussed in reference to those inferred properties of which life, according to the author's system, is compounded.
The second chapter of this section is "on death produced by external causes." The modes by which death is produced by infliction of external injuries on organs, are tnus arranged, either, " 1st. The spirit residing in these surfaces receives a modified supply of blood, as by the general injury, the compression, &c. which the vessels must sustain bv a breach in a structure before continuous; 6'2 Critical Analysis. have expressed our opinions respecting its utility and merit, for it is only necessary to peruse it in order to discern them ; but, as it is itself of an abstract nature, the greater portion of it will not admit of abridgment: we liave therefore been obliged to give a character only of many chapters and sections, instead of an analysis of them. It becomes proper, then, for us to state, that we think it qualified to produce inestimable benefit to medical science. We have perused it several times, and, the more Ave meditate on it, the more earnestly we are disposed to regard it, not merely as an honour to medical literature, or even to the age in which it has appeared, but as one of the; greatest productions of the human mind.
In a work of so extensive a scope as that which this comprises, it must necessarily happen, that the author's opinions are in many instances identical with those of several other philosophers ; and it may appear strange, that we have not, in the foregoing review, noticed any such coincidences. The omission here alluded to has been intentional and premeditated.
The author's opinions are his own ; and he has founded them on ideas and arguments of so original and peculiar a character, that it is useless to trace the similarity that may exist in a few of his deductions to the notions of some of his predecessors; and it must be just as vain to attempt to support or to oppose reasonings like his by the opinions of any other person, as it would be to quote the authority of Newton or Lacepede for or against the propriety of a given solution of a question in geometry.
There is a peculiarity in the style of this work that is somewhat remarkable: it is a plain, easy simplicity, joined with a strength of manner, that is well adapted for the subject. The author seems to have desired to avoid eliciting the attention of the reader from the matter of his discourse by any alluring graces of manner; yet he sometimes evinces a talent for elegance of composition, that is by 110 means of an ordinary character. We know nothing more beautifully eloquent than some passages in the third chapter of the first book; one of which, especially, Ave were much disposed to have transcribed into this article; but the consideration that we had been obliged to pass over in a slight and rapid manner many of the more important parts of the book, prevented its being effected. From the passage here alluded to, and an observation in the Preface, it appears that the author is but thirty-five years of age. If this calculation is correct, his Avork presents a specimen of early development of the understanding, that must be regarded as one of the most admirable of such instances recorded in history; and this will appear more strikingly evident, when it is considered that the too, that medicines of this kind, applied to the stomach for instance, are often the most effectual means of relieving undue action in the uterus, on the princi ple of derivation, or revulsion, just as a blister removes a pleurisy. They therefore act beneficially in a two-fold manner.
In some cases, the author says, this state of the system has given rise to sudden and unexpected dissolution after parturition; and, occasionally, the patient does not recover from ah ill-directed bleeding. Sometimes it terminates fatally, after a more or less urgent or protracted and varied course ; at others, there has been long-continued indisposition. It appears principally under the following forms: " 1, the acute; 2, the more continued; 3, with general symptoms; 4, with some predominantjocal affection; 5, as the effect, chiefly, of intestinal irritation ; or, 6, of hemorrhagy. The greater number of cases-do not, however, admit of being referred to any one of these divisions distinctly or exclusively, but assume a mixed character." All these forms are illustrated by cases, but we cannot take these into particular consideration : we must confine our analysis to a general abstract, and pass on, therefore, to the section relating to the " Description, Symptoms, &c."