Cardan left in his _Dicta Familiaria_ and _Praeceptorum ad filios Libellus_ a long list of aphorisms and counsels, many of which give evidence of keen insight and busy observation of mankind, while some are distinguished by a touch of humour rare in his other writings. He bids his children to be careful how they offend princes, and, offence being given, never to flatter themselves that it has been pardoned; to live joyfully as long as they can, for men are for the most part worn out by care; never to take a wife from a witless stock or one tainted with hereditary disease; to refrain from deliberating when the mind is disturbed; to learn how to be worsted and suffer loss; and to trust a school-master to teach children, but not to feed them. One of the dicta is a gem of quaint wisdom. "Before you begin to wash your face, see that you have a towel handy to dry the same." If all the instances of prodigies, portents, visions, and mysterious warnings which Cardan has left on record were set down in order, a perusal of this catalogue would justify, if it did not compel, the belief that he was little better than a credulous fool, and raise doubts whether such a man could have written such orderly and coherent works as the treatise on Arithmetic, or the book of the Great Art. But Cardan was beyond all else a man of moods, and it would be unfair to figure as his normal mental condition those periods of overwrought nervousness and the hallucinations they brought with them. In his old age the nearness of the inevitable stroke, and the severance of all earthly ties, led him to discipline his mind into a calmer mood, but early and late during his season of work his nature was singularly sensitive to the wearing assaults of cares and calamities. In crises of this kind his mind would be brought into so morbid a condition, that it would fall entirely under the sway of any single idea then dominant; such idea would master him entirely, or even haunt him like one of those unclean spectres he describes with such gusto in the _De Varietate_. What he may have uttered when these moods were upon him must not be taken seriously; these are the moments to which the major part of his experiences of things _supra naturam_ may be referred. But there are numerous instances in which he describes marvellous phenomena with philosophic calm, and examines them in the true spirit of scepticism. In his account of the trembling of the bed on which he lay the night before he heard of Gian Battista's marriage, he goes on to say that a few nights after the first manifestation, he was once more conscious of a strange movement; and, having put his hand to his breast, found that his heart was palpitating violently because he had been lying on his left side. Then he remembered that a similar physical trouble had accompanied the first trembling of the bed, and admits that this manifestation may be referred to a natural cause, _i.e._ the palpitation.