[200] Then they dig, not as the wise men Abraham and Isaac did, making wells, but cisterns, which have no good nutritious stream belonging to and proceeding from themselves, but requiring an influx from without, which must proceed from instruction. While the teachers are always pouring into the ears of their disciples all kinds of doctrines and speculations of science altogether, admonishing them to retain them in their minds, and to preserve them when faithfully committed to memory.