What are called Metaphysics or Pneumatics were set in opposition to Physics, and were cultivated not only as the more sublime, but, for the purposes of a particular profession, as the more useful science of the two. The proper subject of experiment and observation, a subject in which a careful attention is capable of making so many useful discoveries, was almost entirely neglected. The subject in which, after a few very simple and almost obvious truths, the most careful attention can discover nothing but obscurity and uncertainty, and can consequently produce nothing but subtleties and sophisms, was greatly cultivated.

When those two sciences had thus been set in opposition to one another, the comparison between them naturally gave birth to a third, to what was called Ontology, or the science which treated of the qualities