The principle or law of similars is simple and easy of demonstration and yet from Hippocrates to Hahnemann and from Hahnemann to our own time the antipathic mode of treatment has chiefly held sway, perhaps because it is attuned more closely to the innate contrariness of human nature.

Hippocrates, the “Father of medicine”, lived about the fourth century B.C. He is credited with having affirmed that diseases can be cured either by similars or by contraries and that the former are to be preferred.

The principle or law of similars is simple and easy of demonstration and yet from Hippocrates to Hahnemann and from Hahnemann to our own time the antipathic mode of treatment has chiefly held sway, perhaps because it is attuned more closely to the innate contrariness of human nature.

Having become aware and then convinced of the universality of the principle of similia, Hahnemann made an exhaustive search for and a critical examination of noteworthy cures reported from ancient times down to his own day. The vast majority and especially those of outstanding brilliance he found be explained on the basis of the homoeopathic law.

Let us consider a few illustrations of this law, taking some case from the Organon and others from common observation and experience.

We quote from the Sixth Edition of the Organon, beginning on page 85.

“It is not the prolonged application of the degree of cold in which the limb was frozen that restores it isopathically (it would thereby be rendered quite lifeless and dead), but a degree of cold that only approximates to that (homoeopathy) and which gradually rises to a comfortable temperature and thus the limb is recovered by physical homoeopathy.

In like manner, a hand scalded with boiling water would not be cured isopathically by the application of boiling water, but only by a somewhat lower temperature, as for example, by holding it in a vessel containing a fluid heated to 160 which becomes every minute less hot, and finally descends to the temperature of the room, whereupon the scalded part is restored by homoeopathy, the injury resulting from a blow on the forehead with a hard substance (a painful lump is soon diminished in pain and swelling by pressing on the spot for a considerable time with the ball of the thumb, strongly at first and then gradually less forcibly, homoeopathically, but not by an equally hard blow with an equally hard body which would increase the evil isopathically.

Boulduc (1710) perceived that the purgative property of rhubarb was the cause of its power to allay diarrhoea. A Danish Army physician of the name of Stahl (1738) expressed his conviction in the most unequivocal terms: “The rule generally acted on in medicine”, says he, “to treat by means of oppositely acting remedies is quite false and the reverse of what ought to be; I am convinced that diseases will yield to, and be cured by, remedies that produce a similar affection. I have treated tendency to acidity of the stomach by a very small dose of sulphuric acid with the most successful result, in cases where a number of absorbent remedies had been fruitlessly employed”.

Coming now to the living present how often do we hear someone say, “What he needs is a dose of his own medicine,” can conceive of and certainly homoeopathic, the exact similimum if there ever was one.

The next illustration may require a little personal introspection. What faults in others irk and annoy us most? Are they those most similar or dissimilar to our own? Have we some glaring mannerism we would overcome at whatever cost? Her is the prescription. Force ourselves to live for six months or a year with someone cursed with the exact similar of the same or a higher potency. If we refrain from doing violence while suffering a homoeopathic aggravation we will be cured of our grievous fault and a repetition of the remedy will not likely be required.

Stand some distance from your window just at twilight. After a few moments switch on the light. Instantly visibility through the window is reduced commensurate with the brilliancy of the interior. After a short aggravation the eye adjusts itself to the new conditions and a small measure of outside visibility returns. Switch off the light, the room darkens and the window brightens. The inside illumination was homoeopathic to the twilight.

Like cures like and therefore “misery loves company”. NOne but the lonely heart can ever know the depths of despair.

Try imitating a crying child as closely as possible. After swinging a fist or two in your general direction (homoeopathic aggravation) in a moment or so he will begin to laugh and forget all about his original grievance. He is a cured case, thanks to the law of similars.

While Homoeopathic treatment is generally regarded as a system of drug therapy, nevertheless this is taking too narrow a view of the remedial agents possible of employment in harmony with the law of cure rediscovered and expounded by Samuel Hahnemann.

Mechanical conditions and disorders may require mechanical means for their correction and therefore surgery and mechanotherapy may be employed from a homoeopathic standpoint and are then truly beneficent and healing potencies.

Hydrotherapy may and should always be used homoeopathically, never antipathically.

Many cures at the hands of hydrotherapists, naturopaths and eclectics are fundamentally homoeopathic although in many cases no drug substances whatsoever have been employed.

The vast field of psychology offers almost untouched possibilities along the lines of homoeopathic psychotherapy. What a field for research! but let the researcher approach the sacred citadel of the human mind with humility and with a goodly store of common sense. Thoughts are subtle potencies and the spoken word can never be entirely canceled. Regret is powerless to call it back.

Implicit faith in ones physician lends power to that physicians spoken and written word, to every infection and modulation of his voice and to every look and expression on his face.

Nearly everyone is nursing some old grudge or there is something eating or gnawing at the mind, some fancied wrong, some misunderstanding, some real or imagined insult,some mistrust, hatred or jealousy or some silent grief, too deep for words.

If the patient can express and expose this hidden canker to his physician he will be measurably benefited in health by that very expression and should the physician see in that hitherto hidden thing the initial cause of the ensuing disorder he may prescribe the similar drug potency, or if truly worthy of his high calling he may speak the word and the sore is healed.


Eugene Underhill
Dr Eugene Underhill Jr. (1887-1968) was the son of Eugene and Minnie (Lewis) Underhill Sr. He was a graduate of Swarthmore College and the University of Pennsylvania Medical School. A homeopathic physician for over 50 years, he had offices in Philadelphia.

Eugene passed away at his country home on Spring Hill, Tuscarora Township, Bradford County, PA. He had been in ill health for several months. His wife, the former Caroline Davis, whom he had married in Philadelphia in 1910, had passed away in 1961. They spent most of their marriage lives in Swarthmore, PA.

Dr. Underhill was a member of the United Lodge of Theosophy, a member of the Philadelphia County Medical Society, and the Pennsylvania Medical Society. He was also the editor of the Homœopathic Recorder.