"Two difficulties meet one in studying the early history of the science. One is... mysticism... and the other is the custom among the early writers of ascribing their discoveries, books, etc., to fabulous names or ancient heroes and gods. This latter had two objects, the first being to shield the true author in time of persecution, and the second to gain a certain amount of credit and reputation... by the use of the names of such celebrities as Moses, Solomon, Alexander, or Cleopatra. This tendency is especially noticeable among the writers of the Middle Ages, and also the early Greek authors, and is not peculiar to authors of alchemical treatises."