-rr{ <#. ■■■•?.. • : . ; .' V ■ ^v- •>■ !. . ' '' ' ''•■'&&*& .■.'■'■' V#''""' •': |!ft| ;?.:;. ■*■,..■,:, #fe&'^-v^ -y lllfj Si***7 V'c:" t^C^t^ UNITY OF DISEASE, AS OPPOSED TO NOSOLOGY: SUBMITTED TO THE EXAMINATION p REV. JOHN EWING, S. T. P. PROVOST; THE TRUSTEES & MEDICAL FACULTY, OF THE UNIVERSITY OF PENNSYLVANIA, On the thirty-firfl. of May 1800, FOR THE DEGREE OF DOCTOR OF MEDICINE: By ALEXANDER MA Yf-:^. Of Pennsylvania. ,iv ■' '^~?K<^ I f / - ">^'':- E PLURIEUS UNUM. *Jj-c ~^ . PHILADELPHIA: PRINTED BY WAY & GROFF, No. 48, North Third-ltreet. 180O. t ^ » \ \ 9 t TO BENJAMIN RUSH, M. D. Professor of the Institutes and Practice ob Medicine, In the University of Pennsylvania; AS A MARK OF THE RESPECT AND GRATITUDE OF HIS SINCERE FRIEND AND OBLIGED PUPIL : ALSO, TO ARTHUR MAY, M. D. Of Chester, in Pennsylvania; AS A MARK OF FRATERNAL AFFECTION; THE FOLLOWING DISSERTATION is inscribed, BY HIS FRIEND AND BROTHER, ALEXANDER MAY. May 31ft, l8o<3. A DISSERTATION ON THE UNITY OF DISEASE, &c. —^> *<€$■— X HE unity and fimplicity of nature, in all her operations, is obvious to every judicious obferver. The nearer we approach to truth in exploring the phenomena of the univerfe, the greater identity and uniformity we difcover; and the more com- plex our notions, the more the mind becomes in- veloped in error. The frugality of nature is con- fpicuous in all her operations; where one agent is fufficient to affed her purpofe, me never ufes more. The motions of the heavenly bodies, the change of feafons, the fucceffion of day and night, the tides, winds, and the different phenomena of mo- tion, were molt abfurdly explained, till one fingle power was difcovered to be the fole governing prin- ciple of them all. The fcience of chemiftry affords many proofs of this law of unity and fimplicity exifiing throughout the works of nature- A few elementary fubftances are found to be the bafis of all the various forms of matter which compofe the univerfe. 6 All life, animal and vegetable, however varioufly modified, is the effed of one agent, viz. ftimulus. Health and difeafe, are effeds of the fame agent, differing in degree. The fimplicity of nature's ope- rations often prevents their being feen. Men in their inveftigations extend their views beyond the fimplicity of truth, and confequently become loft in error. The circulation of the blood was long a myftery ; but its fimplicity appears to have been the only caufe of its obfcurity: and the phyfiology of the nervous fyftem, the arcanum of the prefent day, probably lies concealed under the fame fimplicity. Some have become infidels in religion, from no other caufe, than that truth was too fimple to be believed. The fame caufe makes men infidels in the fcience of medicine, by leading them beyond the fimplicity of nature for the caufe of difeafe. I. Difeafe is fimply, morbid excitement, or wrong aclion ; or, in other words, it confifts in a morbid ftate of the fyftem, in which fome of its fundions are carried on in an unealy and irregular manner. This morbid excitement, whether it exift in the form of convulfwe aclion, fuffocated aclion^ Jpafm, itching or heat, is the fame thing, and all thefe are effeds of different degrees of force in the remote, or exciting caufes, or of the difference of organiza- tion in the affeded parts ; they all, moreover, occur at different times, under different circumftances of treatment, in the fame form of difeafe j as in gout and yellow fever. 1 From an ignorance of the unity of difeafe, phyfi- cians have fabricated a nofology, dividing difeafe into as many different difeafes as the various forms in which it appears; and arranging them into differ- ent claffes, orders, genera and /pedes, according to their various caufes, feats or fymptoms. Nofology, or a hiftory of difeafes, has long en- gaged the labours of phyficians. The ancient Greek and Roman phyficians began the attempt. Since them, Platerus, Sagar, Sauvages, Sydenham, Baglivi, Linnaeus, Vogel, Cullen, and others, have laboured to bring it to perfedion j but all to very little purpofe. " All of the attemps," fay the learned and ingenious editors of the medical repofitory, " to arrange morbid affedions, have been exceed- ingly imperfed, and it is likely they will al- ways remain fo. We fufped there is a radical dif- ficulty in all thefe nofological attempts, which it is impoflible to remedy ; and that is, that nature has not diftinguifhed fymptom from fymptom, in dif- eafes, with the fame exadnefs, by which plant dif- fers from plant; or one animal, or mineral, varies from another ; but, on the contrary, has interwoven the tifliie of difeafes by threads which are inextrica- ble, but by a more corred and fcientific acquaint- ance with their caufes." It is impoflible to divide difeafes, or give them names which can delineate with any accuracy their 8 different natures, from the different forms of mor- bid adion. Cullen's pyrexia, would lead us to believe, from the definition of the word, that this clafs of difeafes* is always attended with a preternatural degree of heat, which is not the cafe, as all the different orders of this clafs frequently appear with a temperature of the body, that is natural, or preternaturally cool. Yellow fever is a name given to fpecify a particu- lar form of difeafe; but the fymptom from which it derives its name does not occur oftener, perhaps, than once in twenty cafes: here we are liable to be deceived nineteen times in twenty by the name. Fevers have been called intermittent, remittent^ &c. by way of diftindion; but thefe names are not charaderiftic of any particular form of fever; as the fymptoms by which thefe are defignated, occur more or lefs in all forms. Thus the impro- priety and uncertainty of naming difeafe, from any form whatever, might be fhewn, did it not feem like an attempt to illuftrate what muft already ap- pear felf-evident. We might as well exped to comprehend the na- ture of a ftorm, by attending to its various forms, and diftinguifhing them by hard names, as to divide fevers by their remiflions or intermiflions. II. Difeafes have been divided from their remote caufes; but this is improper, as they all ad more or lefs in one way, viz. by Jlimulus. * The plural number is ufed in conformity to cuftom, 9 Dr. Brown fays, " all ftimulant hurtful powers, are participant, but of one effed." Poifons, in- temperance, opium, external violence, miafmata, contagions, viciflitude of heat and cold, and paffions of the mind, all produce difeafes fo fimilar, that the moft difcriminating nofologift could not diftinguifh them. The poifon of the viper produced a dif- eafe fo much like a pleurify, that Dr. Tennant was induced to adminifter the fame remedies in the cure of both. Intoxication, in the fall of 1799, produced a fe- ver with violent convulfions, delirium, and inability to ftand or fpeak. The cure was the fame as if marlh miafmata had been the remote caufe. The lofs of a pint of blood, reftored the patient to the ufe of his feet, fpeech and reafon. A cafe of fever from opium, occurred in 1798 j the remote caufe not being known, it was fufped- ed to be yellow fever: the face was flufhed, the eyes inflamed, the pulfe high ; by copious bleeding, purging and bliftering, the patient recovered, and acknowledged the remote caufe to be a draught of laudanum. Heat and cold, in the extreme, produce fimilar effeds; inflammation, vefication, and pain, are the common effeds of both.* B * The fimilar fenfation produced by the frlgorijle mixture, to that of heat, was experienced by a number of the chemical clafs, as well as my- felf, !aft winter, when the brilliant experiment of freezing mercury, waj perfo*med by the indefatigable and accurate chemift, br. Woodhoufe. The cold produced, caufed the mercury in the thermometer to tall 6<« 10 Bilious fever and pleurify, have different remote caufes; but they have fymptoms exadly fimilar, and are both cured by depletion, which proves that they are the fame difeafe, for even Dr. Cullen admit that " diforders, which are cured altogether by the fame remedies, are of the fame nature." The fever fucceeding a broken bone, furgical operations, as lithotomy, amputation and trepan- ning, has the fame fymptoms as pleurify and bilious fever, and is cured by the fame remedies. The remote caufe of fmall-pox, though different from any other, produces the fame fymptoms that occur from other remote caufes. " The fmall-pox and mealies, are cured by the fame means as pe- ripneumony, or any other fthenic difeafe," fays Brown. And " diforders which are cured altoge- ther by the fame remedies, are of the fame nature," fays Cullen. In the prefent month, a middle aged man, of a robuft habit, was taken ill, with every fymptom of a highly malignant fever, at Chefter in this ftate ; he had drunken fpirits freely through the day ; was bled a quart in the evening,—purged; bled next morning, purged again. The remote caufe was un- known, till the fmall-pox made their appearance. Three days afterwards, he walked out, and complain- ed only of pain from the eruption. In the fame way, phyficians often prevent death, from the fmall-pox, degrees below o; and the mixture felt like coals of fire. This experiment was never performed before in America. II by miftake, without a knowledge of the remote caufe, or the name of the difeafe. That the cure of fmall-pox, is the fame as of other difeafes, is proved by the fuccefs of the pre- fcnt mode of inoculation. By the abftradion of ftimulus, we as certainly leffen the malignity of fmall-pox, as if marfh miafmata had been the re- mote caufe ; and by the addition of any ftimulus, we as certainly aggravate its fymptoms. Even the eruption, which is its fpecific charaderiftic, may be prevented by copious depletion. The puf- tules are the mere effeds of the difeafe. Eryfi- pelas, miliaria, fliingles, nettle-rafh, phlegmon, abfceffes, cancers, buboes, fcrofulous and fcor- butic ulcers, are all local affedions, induced by fever. They are not difeafes, but diforders, the ef- feds of difeafe, and merely accidental circumftance3. " Eruptions, are fevers tranflated to the fkin ; the prickly-heat, the rafh, and the effere of authors, are all ftates of mifplaced fever."f Sydenham calls dyfentery, febris introverfa ; we may with the fame propriety, call eruptive fever, febris extraver- fa. This variety in the effeds of difeafe, is nothing more than pervades all nature; but cannot affed the unity of difeafe, which depends on unity of caufe, and unity of cure. As many different remote caufes, produce fimi- lar effeds at one time, fo at another time, one produces the different effeds of all. f Dr. Rufh's Inquiries and Obfcrvations. Vol. IV. 12 The fame ftimulant power fupports life and health; and, in a different degree, caufes difeafe. The fame remote caufe produces effeds diredly diflimilar : What is more fo, than the cold and hot fits of ague ? The various fymptoms of bilious fever, caufed by marfh miafmata, afford a proof of the fame thing; thefe are apoplexy, coma, convulfions, ri- gour, fore throat, hoarfenefs, giddinefs, faintnefs, delirium, pain in the head, eye-balls, back, hips, limbs, neck and ears, naufea, vomiting, burning in the hands and feet, hemorrhage from the nofe, mouth and bowels.* Thefe are all fymptoms of but one difeafe, and Cullen fays, " that fome fimi- larity of the caufe, argues a fimilarity of diforder produced by it>" A phyfician of a neighbouring village informed me, that the cold of laft January, produced, in the courfe of his pradice, pleurify, rheumatifm, gout, apoplexy, palfy, nephritis, hsemoptyfis, quinfy, pneumony, ophthalmia, hemeplegia, catarrh, ftric- ture in the urethra, and cynanche trachealis, and that depletion cured them all. Thefe could not be different difeafes, for they arofe from one caufe, and were cured by one remedy. A nofologift would have attempted to find names for all thefe different fymptoms; which would have been as ufelefs in leading to a proper mode of treatment, as a know- ledge of the names of the different perfons affeded. * See Dr. Rufh's account of bilious fever. Vol. I. *3 The venereal virus feldom affeds different per- fons in the fame way. One is affeded with go- norrhoea, another with chancres, fome with buboes, others with phymofis, and chordee, whilft many receive no injury, who have all been equally ex- pofed to the fame infedion. All thefe different effeds alfo occur in the fame perfon, at different times, from the fame caufe. Inflammation appears in different forms, as phleg- mon, gangrene and fchirrus. The two latter are only effeds of the former; and the difference in form is caufed by different modes of treatment, the fufceptibility of the parts, and the different degrees of the caufe producing them. Pleafure and pain are both the effeds of one caufe, differing in degree. Thus, friclion when gen- tle gives pleafure ; when violent, pain. So heat, in cold weather, produces both, according to the quantity applied j and cold in hot weather has the fame effed. So uniform is the power that produces difeafe in its operations, that could we afcertain the force of the ading power, and the ftrength or fufceptibility of the fyftem aded on, we might almoft with certainty predid the final iffue of difeafe. When we fee effeds fo fimilar, from caufes fo different, and when we fee thefe effeds removed by the fame mode of treatment, we conclude with Dr. Cullen, " that diforders which are cured altogether by the fame remedies are of the fame nature." *4 When we fee effeds fo different, produced by the fame caufe, we alfo conclude with Cullen, " That fome fimilarity of the caufe argues a fimilarity of the diforder produced by it." And our final con- clufion muft be, that all the remote caufes, however various, unite in their operations, and produce but one difeafe, viz. morbid aclion. III. Difeafes cannot be divided from the predifpof- ing caufe; it is a unit, viz. debility; or a derangement of the equilibrium of excitement and excitability, which is the ftandard of health. This derangement is induced by the power of the remote caufe. When it operates feebly on the fyftem it only induces debi- lity, and the power of the exciting caufe is neceffary to produce difeafe; hence debility is not difeafe, but its predifpofing caufe. IV. Difeafes have been divided from the exciting caufe; but thefe have only one mode of adion,andare reinforcements to the remote caufes, ading by the fame ftimulant power on the accumulated excitabi- lity, and producing the proximate caufe of difeafe. V. Difeafes have been divided from their proxi- mate caufe ; but this is improper, for the proximate caufe is a unit, viz. morbid excitement or the dif- eafe itfelf; and as difeafe which is caufed and cured in the fame manner, is a unit; fo muft the proximate caufe be a unit; but out of this one difeafe, Cullen has fabricated 1387 different difeafes, for many of which he gives a different proximate caufe \ his fuccefs in this attempt may *5 readily be imagined, from his unfortunate choice of spasm for the proximate caufe of fever. Says Cullen again, " But as medicines are only applied to difeafes for the purpofe of removing the proximate caufe, it muft neceffarily be, that difor- ders which are cured altogether by the fame reme- dies are of the fame nature." Here the proximate caufe and nature of the difeafe depend on the fuc- cefs of the medicine. If bark and wine do not cure the remittent and intermittent fevers they are neceffarily difeafes of different natures, with different proximate caufes; but when depletion cures them both, they become one, and when bleed- ing cures yellow fever, bilious fever, gout," and fmall-pox, of neceflity they become difeafes of one nature, with but one proximate caufe. Since the mode of cure has been found to be a unit, the number of drugs is reduced in our (hops, prefcriptions are lefs complex, and the whole fcience is rendered more fimple and intelligible. A ftudent now may acquire more ufeful knowledge in a few years, where fimplicity and unity are taught, than in an age in the fchools of the nofologifts. Here we have theory founded on the firm bafis of reafon and experience, and fads to prove the truth * of our theory. VI. Nofologifts have even given different names to difeafes from their different feats. Pain in the head is called cephalalgia, in the ears otalgia, in the teeth odontalgia, in the limbs rheumatifm, in the feet i6 gout, and in the fide pleurify. We might with the fame propriety give different fpecific names to clouds, from the different parts of the hemifphere they oc- cupy. Spafm in the glottis is named croup, in the bow- els colic, in the lower jaw tetanus, in the limbs cramp, in the extreme veffels, Cullen's proximate caufe of fever. Eruption on the face is eryfipelas, on every part but the face miliaria, on part of the body fhingles, on all the body rafh, prickly heat, and hives. Thefe are all fymptoms or effeds of difeafe, determined to a weak part. To divide thefe different forms into different genera and fpecies, or to call them by different names every time they change their feat, is as abfurd, as to fay a man changes his fpecies whenever he changes his fituation, or to call him by a different name every time we meet him in a different place. Inflammation in the brain is named phrenitis, in the liver hepatitis, in the kidneys nephritis, in the ftomach gaftritis, in the inteftines enteritis, in the lungs pneumony, in the eyes ophthalmia, in the fchneiderian membrane coryza, in the trachea cy- nanche trachealis, and in the tonfils cynanche tonfillaris. All thefe would be treated differ- * ently by a nofologift, according to their names and fituation ; as if fire which breaks out in the kitchen were fpecifically different from that in the parlour, and required different applications to ex- *7 tinguifh it; but fire is ftill the fame thing, and the fimple article water, extinguifhes it with equal fuc- cefs in every part. The form of nervous fever, which is called ty- phus gravior, is reprefented as being a fpecific difeafe; but it is found to be peculiar in nothing but in degree : which inftead of being of the loweft, as has been fuppofed, is ofthehigheft inflammatory type. It occurs in confluent fmall pox, which is the higheft grade of this form of fever. We often find the pulfe raifed by blood-letting in this fever, from a low typhus to a violent fynocha. When the fyftem is ftimulated to the extent of its power, it fuccumbs under the load of greater ftimulus and is proftrated; the pulfe is depreffed; but depletion relieves it, and permits it to ad again with violence. A patient in this form of fever could not fit up for weaknefs; his phyfician defired his pupil to bleed him, he loft 30 ounces of blood, and large bleedings frequently repeated reftored him to perfed health. Dr. Brown mentions a defperate cafe of typhus gravior cured by bleeding, which he fays puz- zled him; and fimilar cafes often occur, which are cured by bleeding, to the utter aftonifhment of all Brunonians and nofologifts who have never ex- perienced the happy effeds of it in this form of fever. Thofe who diftinguifh difeafes from their effeds or fymptoms, are under the necefliry of changing their names as often as the fymptoms vary; but, fivs Cullen, " Charaders in nofology ought not ; C i8 to be ufurped by any means, till after a long con- tinuance of the diforder ; perhaps not till it is finifh- ed." To name a difeafe after it is finifhed!—Are thefe the words of the illuftrious Dr. Cullen ?— How great the abfurdity of nofological arrange- ment, to produce fuch a declaration from fo great a man!—Delenda eft nofologia! To fpecify the genera and fpecies of difeafe from the effeds or fymptoms, is impoflible; becaufe ma- ny which are faid to be of different genera and fpe- cies, have fymptoms exadly fimilar. Hyfterical and hypochondriacal fymptoms frequently occur in gout and malignant ftates of fever. Small-pox and ftone are both attended with fymptoms of ne- phritis ; and the fame difeafe often affeds all parts of the body, as the gout; yet none call it by dif- ferent names ; it is ftill gout, whether feated in the head, ftomach, or extremities. All the different fymptoms of difeafe are but varieties of the fame thing. The fame caufe feldom produces fimilar effeds in different conftitutions, nor in the fame conftitution at different times ; and the fame difeafe appears with different fymptoms in different coun- tries, among different nations, and in different cli- mates and feafons, affeding all varioufly. As when a hurricane invades the oaks of the foreft, all feel the Ihock, and each one (lands, or falls, or breaks, or bends, according to its ftrength :—would a no- fologift divide the caufe of this ftorm into genera and fpecies, from its different effeds ? >9 To prefcribe for the fymptoms of difeafe leads to a moft abfurd mode of pradice. If a patient, after amputation, complained of an itching or a burning fenfation, in the foot; would a nofologift call it gout, and recommend warm flannels to be applied to the partaffeded? If it is improper to fpecify the nature, genera, and fpecies of difeafe, from the effeds, or fymp- toms ; nofology is entirely hypothetical; becaufe on thefe is founded the whole nomenclature of dif- eafes. It is contrary to the nature of things, that effeds, effentially different, can arife, ceteris paribus, from one caufe. Effeds from the fame caufe may vary in form, but can never change the nature of the caufe. Animals and vegetables may change their appearance ; but their nature, genera, and fpecies, remain unchangeable. Animals have never impart- ed their fpecific charaders to others of a different clafs; but one difeafe runs through the different claffes, orders, genera and fpecies of all, and all again unite in one. Hyfteria, the Proteus of dif- eafe, appears in almoft every poflible form; and all the different forms of difeafe, appear in gout. Confumption is often transformed into head-ach, rheumatifm, diarrhea, and mania; and phrenitis, nephritis, gaftritis, and enteritis, are frequent fymp- toms of yellow fever. Were we thus to examine all the difeafes of Cullen's nofology, we fhould not find a fingle fymptom, in any one difeafe, which 20 had not occurred in difeafes of a different name. The changeable forms of difeafe render them inca- pable of divifion into genera and fpecies, or of be- ing defignated by any unchangeable charader. All the different forms muft be taken for a whole ; as foon as a divifion is attempted, the whole is thrown into confufion. " Thefe forms," Tays my preceptor in medicine, " fhould no more be multiplied into different difeafes, than the nu- merous and different effeds of heat and light upon our globe, fhould be multiplied into a plurality of funs."* If the claflification of animals and vegetables; fubftances poffefling uniformly the fame properties, is ftill imperfed and uncertain ; if the line of dif- tindion between animate and inanimate matter, is yet undetermined, how abfurd is it in nofologifts, to attempt a claflification of difeafes, which are ever varying their feats and forms! Nofological arrangements of difeafes, have ren- dered the fcience of medicine incomprehenfible, by unmeaning names, which are never under- ftood, nor exemplified in pradice; they have fe- duced the attention of the phyfician, from an ex- clufive attention to the ftate of the fyftem. They have crouded the fcience of medicine, with myfte- rious difeafes, fuch as opprobria medicorum, difeafes fui generis, and a long clafs of incurables, all of * Medical Inquiries and Obltrvations. Vol. IV, 21 which have originated from nofology, and are only to be removed by adopting the unity of difeafe. " To pronounce a difeafe incurable, is often to render it fo. The intermittent fever, if left to it- felf, would probably prove more frequently, and perhaps more fpeedily fatal, than cancers."* " The want of fuccefs in the treatment of thofe difeafes which are thought to be incurable, is occa- ■ fioned in moft cafes, by an attachment to fuch the- ories as are imperfed, or erroneous."! Confumption, dropfy, gout, rheumatifm and cancers, were long confidered as incurable; but fince thefe have been found to be only different ef- feds of one primary difeafe, they have all yielded to the fame mode of treatment. The unity of difeafe, abolifhes the whole clafs of incurables, and gives the greateft encourage- ment to believe, that what is pradicable in one form of difeafe, may be accomplifhed in every other. A convidion of the truth of this principle, encourages the phyfician to perfevere in the ufe of remedies; and renders him capable of adminifter- ing to his patient, hope, at once animating and falutary. Many patients have been abandoned by their phyficians, from the notion of the difeafe being in- curable ; fome of whom were afterwards cured by nature, accident, or quacks: and others fuffered * Dr. Rufh's Inquiries and Obfervations. Vol. I. f Ibid. Vol. II. Preface. 122 to fall vidims to a difeafe, which probably might have been cured in a few days, had it never been diftinguifhed by a place in nofology. The names of difeafes have often been the caufe of their proving fatal, by leading the nofologifl to treatment contrary to the ftate of the fyftem. A cafe of what is called yellow fever, with depref- kd pulfe, by a nofologifl, is named typhus gravior ; bark and wine are adminiftered, which generally haften the termination of the difeafe in death. Another cafe of the fame form of fever, appears with the fymptoms of what has been called worm fever: pink-root tea is prefcribed for it, which is as effedual in checking the progrefs of the difeafe, as it would be in calming the ocean. If the yellow fever were to receive different names from the different feats and forms in which it appears, it would nearly monopolize all the names in Cullen's nofology. To treat all thefe forms dif- ferently, according to their names, would caufe fuch diverfity, perplexity and uncertainty in prac- tice, as to render it alfo an incurable difeafe. Nofology is the nurfe of empiricifm. Were phy- ficians obliged to prefcribe for the ftate of the fyftem, without naming the difeafe, or if the Chi- nefe cuftom of prefcribing, from feeling the pulfe only, without feeing, or converfing with the pati- ent, were impofed on phyficians, exclufive empiri- cifm could no longer exift. Perfons inattentive to the ftate of the fyftem, would not attempt to cure 23 what they were ignorant of, and men of fcience only, would be confulted by all ranks of people. The notion of a fpecific difference in the nature of difeafe, probably gave rife to the ridiculous pradice of fpecific remedies. Black cat's blood for the cure of fhingles, mares' milk for the hoop- ing cough, fheeps' faffron for the fmall-pox, flower water for the dropfy—have all been pre- ferred by the molt learned phyficians of the laft century ; they were the offspring of nofology ; they have all perifhed ; may nofology fpeedily perifh with them, never to revive again! Nofology is the ignis fatuus of medicine; it is only feen in darknefs; and whilft we purfue the fleeting phantom, it flies with equal fpeed, or finally leaves us plunged deeper in obfcurity. " To defcribe difeafes by any fixed or fpecific charaders, is as impradicable as to meafure the dimenfions of a cloud in a windy day. Much mifchief has been done by nofological arrangements of difeafes. They ered imaginary boundaries between things which are of a homogeneous nature. They degrade the hu- man underftanding, by fubftituting fimple percep- tions, to its more dignified operations of judgment and reafoning. They gratify indolence in a phyfi- cian, by fixing his attention upon the name of a dif- eafe, and thereby leading him to negled the vary- ing ftate of the fyftem."—" The whole materia medica is infeded with the baneful confequences of the nomenclature of difeafes; for every article in it 24 is pointed only againft their names, and hence the origin of the numerous contradidions among au- thors who defcribe the virtues and dofes of the fame medicines."* A belief in the unity of difeafe, will always lead a phyfician to prefcribe for its varying forms and ftages. It will lead him likewife to attend to the effeds of the medicines prefcribed, and to continue or withhold them as circumftances may require. This mode of pradice, it is true, will not be relifhed by the idle praditioner, for it requires frequent vi- fits, and a clofe examination of fymptoms in every form of difeafe; but medicine can never be perfeded in any other way. The benefits of adopting the unity of difeafe will appear farther, in its proftrating what is called the diagnofis of difeafe. A phyfician, inftead of draw- ing on his memory for a hoard of definitions, attends only to the ftate of the fyftem. A knowledge of this is foon acquired, and juft prefcriptions as foon follow. By knowing the caufe of gout, pleurify and malignant fevers to be the fame, it would lead to depletion for each under equal circumftances; it would terminate difputes about difeafe and medi- cine among phyficians, by direding their attention to a fingle objed, and thus remove thofe controverfi.es, in the medical fcience, which nofology is calculated to create. By admitting but one difeafe, we likewife prof- trate the too frequent ufe of the term, " complica- * Dr. Rufli'» Medical Inquiries and Obfervations. Vol. IV. 25 tion of difeafes." This idea has often led to a be- lief, that patients have had as many difeafes, as they have had pains. Thus, yellow fever has been called phrenitis in the morning; gaftritis at noon; colic at night; next nephritis; then rheumatifm; and laft of all convulfions. This fuppofed complication of difeafes, vanifhes on the fifth day in a black vo- mit ; it is then known for the firft time to be a yel- low fever. By admitting the unity of difeafe, we render it lefs neceffary to inveftigate their remote caufes. The bufinefs of a phyfician is to remove their effeds only, except when the caufes continue to ad, and are fub- jed to his controul. Thus the mariner lets go the halyards in a fquall, without regarding the quarter from whence the wind comes. He knows full well that the wind is a unit, and that its mode of deftruc- tion is the fame, whether it blows from the eaft, the weft, the north, or the fouth. Many have feen and lamented the uncertainty, complexity, and obfcurity of medicine; but few have feen its fimplicity and unity. Dr. Balfour re- duced four difeafes, viz. colera morbus, diarrhsea, dyfentery and colic to the inteftinal ftate of fever. Thefe conftitute the febris introverfa of the difcern- ing Sydenham, who likewife had a glimpfe of the unity of difeafe, when he faw that all its different forms, in any feafon, affumed the type of the reign- ing epidemic. This diftant view of unity affords D 26 a more ufeful hint to phyficians, than all the name^ in nofology; it gives us warning when a malignant • epidemic is prevalent, never to confider any difeafe as trifling, and it leads us by the famenefs of its caufe, to the fame mode of cure. It is faid of Dr. Brown, that between the fifteenth and twentieth years of his medical ftudies, " A very obfcure gleam of light, like that of the firft break of day, dawned upon him." Had this gleam been fo bright as to have difco- vered to him, that his two forms of difeafe, fthenic and afthenic, were but one, it would have prevented many of the errors of his fyftem. Mr. John Hunter's " incompatibility of adion," was a near approach to the unity of difeafe, and did honor to his extraordi- nary genius; but truth on the fimplicity and unity of difeafe, never appeared in ks full luftre till it was unfolded, in the ledures and publications of my re- fpeded preceptor,* from whom the principles con- tained in this differtation have been imbibed; for whofe friendly inftrudion, both public and private, I fhall ever feel the warmeft gratitude; to whom the medical world will always be indebted ; and whofe name and memory will be dear to thoufands, long—long after he has bidden adieu to all fublu- nary things. * Dr. Rufh. FINIS. : -: ■■■•:■ -\#tt ■■'■ ■ .--WA *';;C**i& ■;.if£Qii'£*: ■■■> •Irvv.*;,' ^w ■'. •:.,:>.;?*':-iV•'■■.■-' '\rf^.'f M;-'5j