peculiar notions; in 1805 his first work on the subject; in 1810 his
somewhat famous "Organon of the Healing Art;" the next year what he
called the "Pure Materia Medica;" and in 1828 his last work, the
"Treatise on Chronic Diseases." He has therefore been writing at
intervals on his favorite subject for nearly half a century.

The one great doctrine which constitutes the basis of Homoeopathy as a
system is expressed by the Latin aphorism,

"SIMILIA SIBILIBUS CURANTUR,"

or like cures like, that is, diseases are cured by agents capable of
producing symptoms resembling those found in the disease under treatment.
A disease for Hahnemann consists essentially in a group of symptoms. The
proper medicine for any disease is the one which is capable of producing
a similar group of symptoms when given to a healthy person.

It is of course necessary to know what are the trains of symptoms excited
by different substances, when administered to persons in health, if any
such can be shown to exist. Hahnemann and his disciples give catalogues
of the symptoms which they affirm were produced upon themselves or others
by a large number of drugs which they submitted to experiment.

The second great fact which Hahnemann professes to have established is
the efficacy of medicinal substances reduced to a wonderful degree of
minuteness or dilution. The following account of his mode of preparing
his medicines is from his work on Chronic Diseases, which has not, I
believe, yet been translated into English. A grain of the substance, if
it is solid, a drop if it is liquid, is to be added to about a third part
of one hundred grains of sugar of milk in an unglazed porcelain capsule