Michel de Nostredame (December 1503 — July 1566) was a French astrologer, apothecary, physician, and reputed seer, who is best known for his book Les Prophéties (published in 1555), a collection of 942 poetic quatrains allegedly predicting future events. Nostradamus's father's family had originally been Jewish, but had converted to Catholic Christianity a generation before Nostradamus was born. Academic sources argue that Nostradamus's predictions are characteristically vague, meaning they could be applied to virtually anything, and are useless for determining whether their author had any real prophetic powers.