“After a few years spent in the arena of the university, I returned to London for the practice of medicine. The more I observed the facts of this science with an attentive eye, and the more I studied them with due and proper diligence, the more I became confirmed in the opinion which I have held up to the present hour, viz., that the art of medicine was to be properly learnt only from its practice and its exercise; and that, in all probability, he would be the best skilled in the detection of the true and genuine indications of treatment who had the most diligently and the most accurately attended to the natural phenomena of disease.”

The same preface contains Sydenham’s opinion of a great contemporary and valued friend of his. “You know also how thoroughly an intimate and common friend, and one who has closely and exhaustively examined the question, agrees with me as to the method I am speaking of—a man who, in the acuteness of his intellect, in the steadiness of his judgment, in the simplicity (and by simplicity I mean excellence) of his manners, has amongst the present generation few equals and no superiors. This praise I may confidently attach to the name of John Locke.” Dugald Stewart, commenting on this, says: “The merit of the Method therefore may be presumed to have belonged in part to Mr. Locke.” There is no reason, however, in the co-operation of these great minds, for detracting from the praise of either.

Sydenham’s idea of a satisfactory method of curing was a line of practice based upon a sufficient number of experiments. His business was, he says, to support his own observations, not to discuss the opinions of others. The facts would speak for themselves, and would alone show whether he acted with truth and honesty, or, like a profligate and immoral man, was to be a murderer even when in his grave. In the preface to the third edition he says, “The breath of life would have been to me a vain gift, unless I contributed my mite to the treasury of physic.” He considered that medicine was to be advanced in two main ways—by a history of diseases, by descriptions at once graphic and natural, and by formulating a praxis or method of treating them. The most modern thought could produce no sounder principle for describing disease than the following: “In writing the history of a disease, every philosophical hypothesis whatsoever that has previously occupied the mind of the author should lie in abeyance. This being done, the clear and natural phenomena of the disease should be noted—these and these only. These should be noted accurately and in all their minuteness.” He wittily remarks that it often happens that the character of the complaint varies with the nature of the remedies, and that symptoms may be referred less to the disease than to the doctor. He traces the lack of accurate descriptions of diseases to an idea that disease was but a confused and disordered effort of nature defending herself in vain, so that men had classed the attempts at a just description with the attempts to wash blackamoors white.

Sydenham conceived the idea, too, of paying some attention to the wishes and tastes of the patient. “A person in a burning fever desires to drink freely of some small liquor; but the rules of art, built upon some hypothesis, having a different design in view, thwart the desire, and instead thereof order a cordial. In the meantime the patient, not being suffered to drink what he wishes, nauseates all kinds of food, but art commands him to eat. Another, after a long illness, begs hard, it may be, for something odd or questionable; here, again, impertinent art thwarts him and threatens him with death. How much more excellent the aphorism of Hippocrates: ‘Such food as is most grateful, though not so wholesome, is to be preferred to that which is better, but distasteful.’” He has nothing of the meddlesome practitioner about him. “Indeed, if I may speak my mind freely, I have been long of opinion that I act the part of an honest man and a good physician as often as I refrain entirely from medicines, when, upon visiting the patient, I find him no worse to-day than he was yesterday; whereas, if I attempt to cure the patient by a method of which I am uncertain, he will be endangered both by the experiment I am going to make on him and by the disease itself; nor will he so easily escape two dangers as one.”

A fine description of one aspect of hysteria and hypochondria may here be given as an example of his power in the delineation of disease: “The patients believe that they have to suffer all the evils that can befall humanity, all the troubles that the world can supply. They have melancholy forebodings, they brood over trifles, cherishing them in their anxious and unquiet bosoms. Fear, anger, jealousy, suspicion, and the worst passions of the mind arise without cause. Joy, hope, cheerfulness, if they find place at all in their spirits, find it at intervals ‘few and far between,’ and then take leave quickly. In these, as in the painful feelings, there is no moderation. All is caprice. They love without measure those whom they will soon hate without reason. Now they will do this, now that—ever receding from their purpose.... All that they see in their dreams are funerals and the shadows of departed friends.”

The great physician has nowhere described his own character more clearly than in the following passage: “In all points of theory where the reader finds me in error, I ask his pardon. In all points of practice I state that I speak nothing but the truth; and that I have propounded nothing except what I have properly tried. Verily, I am sure that, when the last day of my life shall have come upon me, I shall carry in my heart a willing witness that shall speak, not only to the care and honesty with which I have laboured for the health of both rich and poor who have intrusted themselves to my care, but also to those efforts which I have made to the best of my power, and with all the energies of my mind, to give certainty to the treatment of diseases even after my death, if such may be. In the first place, no patient has been treated by me otherwise than I would myself wish to be treated under the same complaint. In the second, I have ever held that any accession whatever to the art of healing, even if it went no further than the cutting of corns or the curing of toothaches, was of far higher value than all the knowledge of fine points, and all the pomp of subtle speculations—matters which are as useful to physicians in driving away diseases, as music is to masons in laying bricks.”

The last comparison leads us to note that a vein of humour runs through Sydenham’s works, as when he quotes

“Tua res agitur paries quum proximus ardet,”

as a reason for his leaving London in the height of the plague.

In another passage, he is referring to the want of opportunity of the poor to injure themselves by unsuitable diet in smallpox, owing to the “res augusta domi.” Yet even among the poor, he says, since they learnt the use of certain cordials, many more have died than in previous ages less learned but more wise. “Nowadays every house has its old woman,” he says, “a practitioner in an art she never learnt, to the killing of mankind.”