There is no aspect of the history of Dr. Hahnemann’s medical discoveries that is less known, less understood, and more ignored and denied than the curious story of his use of dual remedies. It is a story that has critical implications for understanding both his earlier and his later insights and writings. It is a story that has only been partially told and then that part only in disjointed bits and pieces. Thanks to extensive research several years ago, the whole story was published in the book, An Affair to Remember: The Curious History of the Use of Dual Remedies, Its Significance and Suppression.
Historical understanding is one of the three pillars of human comprehension according to the Greeks, the other being didactical (rational explanation) and polemical (critical analysis).
The story of dual remedies starts ostensibly in the Spring of 1833 with the receipt by Dr. Hahnemann of a letter from one of his closest proteges, Dr. Julius Aegidi. Dr. Hahnemann was at the pinnacle of an illustrious career, having written the Organon and also the radical Chronic Diseases, which insights were the basis for a revised edition of the Organon, its fifth since 1810, but the first major revision of this seminal work. Hahneman was just completing these revisions, and in his 78th year could look back with pride on what he had accomplished.
Aegidi was an Italian physician converted to homeopathy through Hahnemann’s cure of his psoric disease in 1823. He subsequently became an enthusiastic supporter of Hahnemann, perhaps the closest, next to Boenninghausen  , as shown in the intimacy of letters exchanged and the personal relationship developed with the founder of homeopathy. At the time of our story, Dr. Aegidi was working in Düsseldorf, Germany thanks to Hahnemann’s personal interventions with certain of the aristocracy in that city.
Dr. Aegidi’s letter was most remarkable. Dated 15 May 1833, the letter reported on 233 cured cases. That, in and of itself, was not remarkable. However, the method of cure used by Aegidi was: two highly potentized substances at the same time.
Hahnemann replied in a letter a month later, 15 June 1833  . His reply was equally, if not more, remarkable. Hahnemann assured Aegidi that he welcomed the approach and that it was entirely consistent with his previous teachings. Anyone with a passing knowledge of homeopathy would be forgiven for expressing surprise at this point and perhaps suspecting an April Fool’s prank. In this light, let’s consider the reply and the ensuing events in some detail. First, we have the text of Hahnemann’s reply:
Dear Friend and Colleague,
Do not think that I am capable of rejecting any good thing from mere prejudice, or because it might cause alterations in my doctrine. I only desire the truth, as I believe you do too. Hence I am delighted that such a happy idea has occurred to you, and that you have kept it within necessary limits; ‘that two medicinal substances (in smallest dose, or by olfaction) should be given together only in a case where both seem Homoeopathically suitable, but each from a different side.‘ Under such circumstances the procedure is so consonant with the requirements of our art that nothing can be urged against it; on the contrary, homoeopathy must be congratulated on your discovery. I myself will take the first opportunity of putting it into practice, and I have no doubt concerning the good result. I am glad that von Boenninghausen is entirely of our opinion and acts accordingly. I think, too, that both remedies should be given together; just as we take Sulphur and Calcarea together when we cause our patients to take or smell Hepar sulph, or Sulphur and Mercury when they take or smell Cinnabar. Permit me then to give your discovery to the world in the fifth edition of the ‘Organon,’ which will soon be published. Until then, however, I beg you to keep it to yourself, and try to get Mr. Jahr, whom I greatly esteem, to do the same. At the same time I there protest and earnestly warn against all abuse of the practice by a frivolous choice of two medicines to be used in combination. (Haehl, Vol. II, p. 85, bold added)
I too have made a beginning with smelling two suitably combined remedies, and hope to have some good results. I have also dedicated a special paragraph in the fifth edition of the ‘Organon,’ to this method, and in this way introduced it to the world. (Haehl,, Vol. II, p. 253, bold added)
We shall see later that Boenninghausen had already been doing similar work with dual remedies in mixtures, and that Hahneman was fully aware of this. For the moment, let’s look at what Hahnemann proposed to put in the new, 5th edition of the Organon, then already being readied for publication. The new paragraph on the use of two remedies together was to have been as follows:
Section 274b. There are several cases of disease in which the administration of a double remedy is perfectly Homoeopathic and truly rational; where, for instance, each of two medicines appears suited for the case of disease, but each from a different side; or where the case of disease depends on more than one of the three radical causes of chronic disease discovered by me, as when in addition of psora we have to do with syphilis or sycosis also. Just as in very rapid acute diseases I give two or three of the most appropriate remedies in alternation; i.e., in cholera, Cuprum and Veratrum; or in croup, Aconite, Hepar sulph. and Spongia; so in chronic disease I may give together two well-indicated Homoeopathic remedies acting from different sides, in the smallest dose. I must here deprecate most distinctly all thoughtless mixtures or frivolous choice of two medicines, which would be analogous to Allopathic polypharmacy. I must also once again particularly insist that such rightly chosen Homoeopathic double remedies must only be given in the most highly potentized and attenuated doses.” (Thomas L. Bradford, The Life and Letters of Hahnemann, p. 486, bold added)
While Aegidi’s letter marks the formal beginning of our story, the origins of this momentous part of Hahnemann’s life and works can be discovered to lie in his very early works. However, the implications of his discoveries of 1796 only bore fruit years later. We’ll pick up the story several years before Aegidi sat down to write about his discoveries with the use of two remedies in mixture.
Both Hahnemann and Boenninghausen were aware of what Aegidi was doing well before Aegidi wrote his letter on the 233 cured cases. According to Boenninghausen, writing to Hahnemann, a certain Dr. Stoll of Cologne:
…had suggested dividing the remedies into two classes, the one of which should act upon the body and the other upon the soul. He thought that these two kinds of medicine should be combined in a prescription in order to supplement each other.
His method making some noise in Cologne, and Dr. Aegidi, then at Düsseldorf, having in vain endeavoured to discover the essential secret of this novelty, the latter induced me to endeavour to find out. I succeeded in doing so. (Bradford, p. 492)
Hahnemann indicates his awareness of the matter in an earlier letter to Aegidi of 28 April 1833. At this point, Hahnemann is cautious about the use of mixtures given his general criticisms of polypharmacy and his wariness over the ability of others to undermine the hard fought gains he had made in medical reform.
Do not cease from announcing publicly in great detail your work in the Düsselthal institution. But do cease to pay any attention to Dr. Stoll’s mixtures; otherwise I might fear that you were not yet convinced of the eternal necessity of treating patients with simple unmixed remedies. I have seen even shepherds and hangmen do some wonderful things now and then. Are we to chance to luck in the same way? (Haehl, Vol. I, p. 393)
In this same letter, Hahnemann indicates his general concern to maintain the purity of his system against allopathy, echoing the struggles he was having in this regard:
The purifying and separating of the true from the false which I undertook with the highest motives and which has the unmitigated approval of the best and most dependable of my students, must draw the world’s attention to real values. What have you to fear from a frank and earnest separation of pure homoeopathy from that humbugging which must be the grave of homoeopathy if it is allowed to continue advertising itself as genuine and gradually insinuating allopathy again — a very convenient resource for the sluggards? The science and I have need of fewer but truer adherents, I do not wish to see my colleagues increased by a large number of those false coiners. I wish to count as mine only a few good men and true. (Haehl, Vol I. p. 256)