[895] Dr. Robert Williams (Encyclopædia of the Medical Sciences, London, 1847, 4to, p. 688) says, ‘The diagnosis between gout and rheumatism is often exceedingly difficult, so much so that nosologists have given a mixed class, or rheumatic gout. Mr. Hunter warmly opposed this compound appellation, for, in his opinion, no two distinct diseases, or even distinct diatheses, can co-exist in the same constitution; a law, it must be admitted, to have many exceptions.’ Compare Watson's Principles and Practice of Physic, London, 1857, vol. i. p. 312; ‘acting upon the aphorism of John Hunter (an aphorism, however, which requires some qualification), that two diseases or actions cannot go on in a part at the same time.’ According to another authority, ‘There can be little doubt that two or more zymotic processes do often go on simultaneously in the blood and body; a fact of profound interest to the pathologist, and worthy of attentive investigation.’ Report on the Public Health for 1847, in Journal of the Statistical Society, vol. xi. p. 168, London, 1848. See also, on the co-existence of specific poisons, Erichsen's Surgery, 2nd edit., London, 1857, p. 430. Mr. Paget, in his striking and eminently suggestive Lectures on Pathology, London, 1853, vol. ii. pp. 537, 538, has made some interesting remarks on one part of the theory of co-existence; and his observations, so far as they go, tend to corroborate Hunter's view. He has put very forcibly the antagonism between cancer and other specific diseases; and especially between the cancerous diathesis and the tuberculous.
[896] ‘The most simple sympathy is perhaps to be found in vegetables, these being much more simple than the most simple animal.’ Principles of Surgery, in Hunter's Works, vol. i. p. 327.
[897] ‘This principle of action, called sympathy,’ &c. Ibid. vol. i. p. 318.
[898] ‘Sympathy may be divided into two kinds, the natural and the diseased.’ Principles of Surgery, in Hunter's Works, vol. i. p. 320; see also A Treatise on the Blood, Inflammation, &c., in Works, vol. iii. p. 6.
[899] Croonian Lectures on Muscular Motion, in Hunter's Works, vol. iv. p. 207; and exactly the same words in his Phytology, in Hunter's Essays, London, 1861, vol. i. p. 361.
[900] ‘Local or partial sympathy is found more in old than in young; whereas universal sympathy is more in young than in old. Sympathy is less determined in young persons, every part being then ready to sympathize with other parts under disease.’ … ‘As the child advances, the power of sympathy becomes partial, there not being now, in the constitution, that universal consent of parts, but some part, which has greater sympathy than the rest, falls into the whole irritation; therefore the whole disposition to sympathy is directed to some particular part. The different organs acquire more and more of their own independent actions as the child grows older.’ Hunter's Works, vol. i. pp. 322, 323.
[901] ‘Susceptibilities for dispositions and actions appear to me to be the same with what are usually understood by temperament. Temperament is the state of the body fitting it for the disposition or action it is then in.’ Hunter's Works, vol. i. p. 307.
[902] Hunter's Works, vol. iii. p. 393.
[903] ‘As every natural action of the body depends, for its perfection, on a number of circumstances, we are led to conclude, that all the various combining actions are established while the body is in health, and well disposed; but this does not take place in diseased actions, for disease, on the contrary, consists in the want of this very combination.’ Hunter's Works, vol. iii. p. 10. Compare vol. i. p. 310: ‘I have explained that a disease is a disposition for a wrong action, and that the action is the immediate effect of the disposition, and that either the actions or the effects of those actions, produce the symptoms which are generally called the disease; such as sensations, which are commonly pain of all kinds, sickness, alteration visible or invisible in the structure of the part or parts that act, and sympathy.’
[904] ‘There is no such thing, strictly speaking, as a predisposing cause. What is commonly understood by a predisposing cause is an increased susceptibility to form disposition to action. When I say I am predisposed for such and such actions, it is only that I am very susceptible of such and such impressions.’ Hunter's Works, vol. i. p. 303. See also p. 301: ‘The most simple idea I can form of an animal being capable of disease is, that every animal is endued with a power of action, and a susceptibility of impression, which impression forms a disposition, which disposition may produce action, which action becomes the immediate sign of the disease; all of which will be according to the nature of the impression and of the part impressed.’