88 PATHOLOGY. 
not reafonable for ns to believe, that t-hofe beings were 
born for no other purpofe than to die; or that it is within, 
the defign of nature that the pangs of production on the 
part of the mother fltould, on that of her offspring, be 
almoft immediately fpcceedbd by the ltruggle of diffblu- 
lution. Fault mud exilt fomevvhere : it cannot be in the 
providence of God; it mu ft therefore-attach to the im¬ 
providence and indifcretion of man. Confequences as 
fatal originate from ignorance as from .crime. Infanticide, 
when perpetrated under the impulfe'of maternal defpera- 
tion, or in the agony of anticipated difgrace, is a fubjeft 
of aftonifhment and horror ; but, if a helplefs viftim be 
drugged to death, or poifoned by the forced ingurgitation 
of nauleous and effentially-noxious potions, we lament 
the refult merely, without thinking about the means 
which inevitably led to its occurrence. Confcience feels 
little concern in cafes of medicinal murder. The too- 
ordinary habit of jelling upon thefe fubjefts in convivial 
or familiar converfation, has an unhappy tendency to 
harden the heart,and inclines us to regard, with an inhu¬ 
man and indecorous levity, thofe dark and horrible cataf- 
trophes which too frequently arife from profeffional igno¬ 
rance or miftakeT Efiays on Hypochondrialis ; 2d edit. 
1821. 
Some other fyftems of inferior importance have appeared 
in different countries, efpecially in Germany. We pafs 
over them, however ; and, difmifting this uninterefting 
branch of our fcience, retrace our Heps to conlider the 
moll important of the modes in which difeafe, or a change 
from the phenomena of healthy action, may arife. 
An inquiry into the abllraft principles of difeafe is a 
fubjeft of acknowledged difficulty. The very definition 
of the word difeafe involves more trouble than might at 
firft feem apparent, and is indeed a matter about which 
there exifts much difference of opinion. We content 
ourfelves, therefore, with the life of the laconic definition, 
that difeafe is the abfence of health, acknowledging, how¬ 
ever, that this defcription involves the definition of 
what health is. But the latter queftion is anfwered by 
Phyfiology, a fcience with which the. pathologift is fup- 
pofed to be previoully acquainted. 
We do not propofe to enter into a confideration of the 
minute and remote caufes of difeafe. It would not per¬ 
haps be difficult to lhow, that the firft changes which 
take place in the various ftruftures mull operate by their 
relation with the vital properties. This, of courfe, ap¬ 
plies principally to thole caufes which produce what is 
called the predifpojition to difeafe. A predij'pofing cuvj'e is 
that which renders the body liable to be attacked by dif¬ 
eafe, or to be afted upon by an exciting caufe ; for the 
operation of an exciting caufe alone is generally not fuf- 
ficient to produce difeaie. Thus feveral perfons may be 
expofed at thefame time to the fame external agents, e. g.* 
to cold and moifture : in forne, thefe agents will excite 
difeafe ; on others they will aft with impunity. In the 
former perfons, fome circumftances mull have exifted 
which rendered them liable to receive thofe morbid im- 
preffions; in the latter, no fuch predifpofition was pre- 
fent. Again, fome of thofe, whom the exciting caufes 
affefted, may fuffer one kind of difeafe, and others a dif¬ 
ferent one; thus, one individual may be afflifted with 
rheumatifm, another with catarrh, a third with dyfentery, 
and fo on ; fafts implying the exiftence of fome peculiar 
condition of the body, or of the organs refpeftively at¬ 
tacked, w hich is juftly deemed a predifpofing caufe of the 
particular malady which may have occurred. In fome 
inftances, the predifpojition is obvious and well under- 
ftood : thus one attack of rheumatifm, pleurify, or any 
inflammatory diforder, generally renders the body more 
liable to fuffer a fecond : a peculiar formation of thecheft, 
combined with a fair and delicate fkin, with dark eyes, 
lively fpirits, &c. implies a tendency to be affefted with 
pulmonary confumption : and a plethoric habit, large 
head, Ihort neck, very florid complexion, &c. threatens 
the acceffion of apoplexy. In fuch circumftances the 
kinds of exciting caufes, which ought to be peculiarly 
avoided, are manifeft ; and by a careful attention to this 
fuggeftion, the difeafes, with which the individuals are 
menaced, may be often avoided. 
The exciting is the next mode of remote caufation, and 
is of courfe an agent which operates for the moll part by 
the relation it holds with the predifpofing caufe. The ex¬ 
citing caufes of difeafe have given rile to many and va¬ 
rious hypothefes. Hippocrates fuppofed that diet and 
air were the externals whence difeafe w\as principally de¬ 
rived ; and certainly, as thefe are the pabula vita:, as they 
conllitute the repair necefiary to our exiftence, an unufual 
Hate of them mull produce a correfponding change in the 
fenfations and funftions of our bodies. We can only 
therefore add to thefe exciting caufes, mental impre.ff.ons 
and exceffive aftion, or the reverfe, of certain organs. 
But there are fome exciting caufes fo very generally af- 
fefting mankind as to lead us to fuppofe that they operate 
independently of any ftate of predifpofition ; as the poifon 
of fyphilis, fmall-pox, rabies, &c. Though even thefe 
difeafes do not feem uninfluenced by the Hate of confti- 
tution, as they exilt in various degrees of intenfity in 
different individuals. 
As thefe exciting caufes of difeafe can come only from 
without, they mult operate in the firft inltance through 
the medium of thofe parts by which man is related with 
the external world. Thefe are the organs of fenfe, and 
thofe unions of the three fundamental ftruftures which 
have been denominated the alimentary canal , the pulmonary 
cavity, and the cutaneous expavjion. As thefe three ftruc- 
tures are all affimilation or abforption, and at the fame 
time abundantly fupplied with nerves, they mult commu¬ 
nicate morbid impreffions, either, ill, by ailimilating fub- 
llances of an improper nature ; of which we have frequent 
inftances in the reception of poifons, &c. into the blood, 
in thetranfmiffion of the marlh miafmata, or the contagion 
of fevers, &c. or 2dly, by tranfmitting nervous impreffions 
to the brain, and inducing diforder of that organ, and the 
nervous fyllem generally. Each of thefe modes may, ac¬ 
cording as predifpofing caufes are in exiftence,' produce 
local difeafe, or dilturbance of general funftions. 
But it is very obvious, that, however firmly thefe no¬ 
tions may be eftablilhed, we advance but a very little 
way in attaining a knowledge of exciting caufes. Bor, 
fo various are the modes by which externals may operate, 
fo many infcrutable and various properties belong to 
food, and Hill more to air, and fo numerous mull be the 
derangements produced by nervous excitation, that the 
attempt to trace the law's of thefe caufes will for ever re¬ 
main inefficient. 
The operation of the fenfes can of courfe only induce 
diforder of the brain and nervous fyllem by exhaulling 
its energies ; whether that exiiaullion be produced by 
excitement of the brain generally, or of its particular 
parts ; or, on the other hand, by the depreffion of them. 
To illuftrate thefe principles, we will fuppofe a patient 
afflifted with a ftate of the liver predijpojc.d to difeafe. Is 
mental emotion by exceffive grief, that is to fay, is the 
produftion and tranfmiffion of nervous energy, dillurbed 
by the inordinate aftion of the brain? the procefls of 
fecretion in the liver will be obftrufted ; and thus induce 
firnple local plethora, perhaps the fimpleit form of difeafe. 
On the other hand, difeafe may occur in the predij'pofed 
liver by the immediate application of an improper mate¬ 
rial received into the blood, and afting as an unufu'al 
Itimulus to the contraftile power of the capillary velfels 
of the liver; hence, in the fame way,impeding fecretion, 
&c. 
Of the application, however, of thefe doftrines, we 
fhall have occafion to give very frequent illuftration in 
the pathology of particular difeafes. We have now to 
conlider the nature of what is called the proximate caufe 
of difeafe. The precife meaning attached to this term 
is, that it delignates an adtion of the body, in contra-dil- 
tinftion to Hates of impreffions which conllitute remote 
caufes. 
