In 1818, when my chief work first appeared, Animal Magnetism had only begun to struggle into existence. But, as to its explanation, although, to be sure, some light had been thrown upon the passive side of it, that is, upon what goes on within the patient, by the contrast between the cerebral and the ganglionic systems, to which Reil had drawn attention, having been taken for the principle of explanation, the active side, the agent proper by means of which the magnetiser evokes all these phenomena, was still completely shrouded in darkness. People groped about among all sorts of material principles of explanation, such as Mesmer's all-permeating cosmic ether, or the exhalations from the magnetiser's skin, assumed by [Thomas] Stieglitz to be the cause, &c. &c. At the utmost a nerve-spirit had been recognised and, after all, this was but a word for an unknown thing. The truth had scarcely begun to dawn upon a few persons, whom practice had more deeply initiated. But I was still far from hoping for any direct corroboration of my doctrine from Magnetism.
Dies diem docet [one day teaches another] however, and the great teacher, experience, has since brought to light an important fact concerning this deep-reaching agent which, proceeding from the magnetiser, produces effects apparently so contrary to the regular course of Nature that the long lasting doubt as to their existence, the stiff-necked incredulity, the condemnation of a Committee of which Lavoisier and Franklin were members, in short, the whole opposition that Magnetism encountered both in its first and second period (with the sole
