The followers of Herophilus and Erasistratus, though they founded schools, did not greatly influence the art of medicine, nor did they contribute much to its advancement beyond the point in which it was left by their great masters. They fell into fruitless speculations instead of pursuing their science by accumulating facts; in the words of Pliny, it was easier “to sit and listen quietly in the schools, than to be up and wandering over deserts, and to seek out new plants every day.”[420] So Dogmatism fell into disrepute and made way for the advent of Empiricism. SCHOOL OF THE EMPIRICS. The School of the Empirics was the outcome of the system of Scepticism, introduced by Pyrrho and extended by Carneades, who taught that there is no certainty about anything, no true knowledge of phenomena, and that probability alone can be our guide. Ænesidemus carried this scepticism into the medicine of the Empirics, but the school was originally established under the title of the Teretics or Mnemoneutics. The Empirics rested their system on what was called the “Empiric tripod,”—that is, accident, history, and analogy. Remedies have come to us by chance, by the remembrance of previous cures, and by applying them to similar cases. The sect of the EMPIRICISTS was founded by Serapion of Alexandria and Philinus of Cos in the third century B.C. They were in opposition to the Dogmatists, professing to derive their knowledge only from experience; they held that the whole art of medicine consisted in observation, experiment, and the application of known remedies which have constantly proved valuable in the treatment of one class of diseases to other and presumably similar classes. Celsus,[421] in his account of the principles of this sect, says that “they admit that the evident causes are necessary, but deprecate inquiry into them because nature is incomprehensible. This is proved because the philosophers and physicians who have spent so much labour in trying to search out these occult causes cannot agree amongst themselves. If reasoning could make physicians, the philosophers should be the most successful practitioners, as they have such abundance of words. If the causes of diseases were the same in all places, the same remedies ought to be used everywhere. Relief from sickness is to be sought from things certain and tried, that is from experience, which guides us in all other arts. Husbandmen and pilots do not reason about their business, but they practise it. Disquisitions can have no connection with medicine, because physicians whose opinions have been directly opposed to one another have equally restored their patients to health; they did not derive their methods of cure from studying the occult causes about which they disputed, but from the experience they had of the remedies which they employed upon their patients. Medicine was not first discovered in consequence of reasoning, but the theory was sought for after the discovery of medicine.