In the first century after Christ, Aretaeus carried these ideas yet further, observed the phenomena of insanity with great acuteness, and reached yet more valuable results.

Near the beginning of the following century, Soranus went still further in the same path, giving new results of research, and strengthening scientific truth.

Toward the end of the same century a new epoch was ushered in by Galen, under whom the same truth was developed yet further, and the path toward merciful treatment of the insane made yet more clear.

In the third century Celius Aurelianus received this deposit of precious truth, elaborated it, and brought forth the great idea which, had theology, citing biblical texts, not banished it, would have saved fifteen centuries of cruelty--an idea not fully recognised again till near the beginning of the present century--the idea that insanity is brain disease, and that the treatment of it must be gentle and kind.

In the sixth century Alexander of Tralles presented still more fruitful researches, and taught the world how to deal with melancholia; and, finally, in the seventh century, this great line of scientific men, working mainly under pagan auspices, was closed by Paul of Aegina, who under the protection of Caliph Omar made still further observations, but, above all, laid stress on the cure of madness as a disease, and on the absolute necessity of mild treatment.
(342) It is significant of this scientific attitude that the Greek word for superstition means, literally, fear of gods or demons.
Such was this great succession in the apostolate of science: evidently no other has ever shown itself more directly under Divine grace, illumination, and guidance.