The number of practical, sensible men who have, even in recent times, believed themselves under the special care and protection of a genius or guardian angel, is much larger than is commonly known. The ancients looked upon a genius as a part of their mythology; and modern Christians, who cherish this belief, refer to the fact that the Saviour said of little children: "In heaven their _angels_ do always behold the face of my Father" (Matt. xviii. 10). These visions--for so they must be called--vary greatly in different persons. To some men they appear only when great dangers are threatening or sublime efforts have to be made; while in others, they assume, by their frequency, a more or less permanent form, and may even be inherited, becoming tutelary deities of certain houses, familiar spirits, or specially appointed guardian angels of the members of a family or single individuals. Hence, the well-known accounts of the genius of Socrates and the familiar spirits of the Bible, in ancient times. Hence, also, the almost uninterrupted line of similar accounts through the Middle Ages down to our own day. Thus, Campanella stated that whenever he was threatened with misfortune, he fell into a state half way between waking and sleeping, in which he heard a voice say: "Campanella! Campanella!" and several other words, without ever seeing a person. Calignan, Chancelor of Navarre, heard in Béarn, his name called three times, and then received a warning from the same voice to leave the town promptly, as the plague was to rage there fearfully. He obeyed the order, and escaped the ravages of the terrible disease (Beaumont, "Tractat.," etc., p. 208). The Jesuit Giovanni Carrera had a protecting genius, whom he frequently consulted in cases of special difficulty. He became so familiar with him, that he had himself waked every night for his prayers, but when at times he hesitated to rise at once, the spirit abandoned him for a time, and Carrera could only induce him to come back by long-continued praying and fasting ("Hist. S. J.," iii. p. 177).