The _symptoms alone_ are absolutely useless in any case of real difficulty. Of that Abernethy was well aware, and he did much to guard us against the error into which a reliance on them was calculated to lead. He knew that organs which were diseased would sometimes afford indications not distinguishable from those of health; and that, conversely, organs essentially sound would sometimes only afford those signs which were indicative of disorder. We have, we trust, made some little progress in this very difficult branch of inquiry; and although it is true that organic disease not unfrequently escapes detection during life, yet, so far as we have observed, it is only in those cases in which there is, notwithstanding the daily lessons of experience, an _improper reliance_ on what are called the symptoms. We assert, without the least hesitation, that organic diseases should seldom elude detection where the investigation is sufficiently comprehensive; but it must include _all the facts_ of the case, the early history, and such circumstances which, however remote, have been over and over again proved to be capable of exerting an influence on the body; an investigation which, however vainly pleaded for in medical science, however regarded as too exacting, involves nothing more in principle than is required as a matter of course _in all other_ scientific investigations. When these conditions are observed, it is very rarely that we cannot detect organic affections in organs in which there may be no _present_ symptoms. In relation to the _extent_ to which they may be affected, it is true we have yet much to learn; still, if cases be judged of not by the history _merely_, nor by the symptoms _merely_, but by both in conjunction, and if to these be added a careful observation of the _amount_ of work that the organs are separately or collectively doing, as _compared with their natural proportions_; together with a careful estimate of that which the actions of any visible disease may be eliminating from the body; then, indeed, we have good ground for hope that means will be opened to us of distinguishing more accurately various states of the system; and additional principles and powers disclosed of readjusting the disturbed balance of the various functions, which is the essential element of disease. [Footnote 29: "History of the Inductive Sciences."] [Footnote 30: Butler's "Analogy."] CHAPTER XVI. "MY BOOK" CONTINUED. "La première chose qui s'offre à l'Homme quand il se regarde, c'est son corps. Mais pour comprendre ce qu'elle est, il faut qu'il la compare avec tout ce qui est au-dessus de lui, et tout ce qui est au-dessous, afin de reconnoître ses justes bornes."—PASCAL, PENSÉES, NATURE DES HOMMES, vol. ii, p. 57.