By means of a historical, classical philological and philosophical approach, this paper attempts to demonstrate that homeopathy is based on three powerful traditions of thinking, which can be traced back to Ancient Greece's pre-Socratic era. Actually, it seems to be constituted by what may be termed lógos -, hómoion - and iásthai -thinking: that is, thinking in terms of rationality, similarity and healing. By contrast, modern medicine tends to be aligned with just one of these traditions, at the expense of the others, this being not without risk and adverse effects. It is mainly determined by the first type of rationality that genealogically derives from, and is therefore compatible with, the logic of economics whose predominance in the health care systems of modern societies is progressively rising. Homeopathy, however, may not be sufficiently and fairly understood without taking into account the complementary forms of thinking on which it also rests, such as the principle of similarity in an all-encompassing sense, and ancient healing knowledge in the tradition of catharsis. As a corollary of being essentially constituted by the three, homeopathy may persistently be in need of a dynamic equilibrium of its three constituent bases. Attempts to approach homeopathy from only one of the indicated modes of thinking fail to grasp its essence and result in figments or caricatures of what homeopathy was originally meant to be.