The year 1555 may be held to mark the point of time at which Cardan reached the highest point of his fortunes. After a long and bitter struggle with an adverse world he had come out a conqueror, and his rise to fame and opulence, if somewhat slow, had been steady and secure. He longed for wealth, not that he might figure as a rich man, but so that he might win the golden independence which permits a student to prosecute the task which seems to subserve the highest purposes of true learning, and frees him from the irksome battle for daily bread. He loved, indeed, to spend money over beautiful things, and there are few more attractive touches in the picture he draws of himself than the confession of his passion for costly penholders, gems, rare books, vessels of brass and silver, and painted spheres.[176] In this brief season of ease and security, there were no flaming portents in the sky to foretell the cruel stroke of evil fortune which was destined so soon to fall upon him.

Cardan has left a very pathetic sketch of his own miserable boyhood in the strangely ordered home in Milan, with his callous, tyrannical father, his quick-tempered mother, and the superadded torment of his Aunt Margaret's presence. Fazio Cardano was a man of rigorous sobriety, and he seems moreover to have atoned for his early irregularities by the practice of that austere piety which Jerome notices more than once as a characteristic of his old age.[177] The discipline was hard, and the life unlovely, but the home was at least decent and orderly, and no opportunities or provocations to loose manners or ill doing existed therein. In Cardan's own case it is to be feared that, after Lucia's death, the affairs of his household fell into dire confusion, in spite of the presence of his mother-in-law, Thadea, who had come to him as housekeeper—her husband, Altobello, having died soon after the marriage of his daughter with Cardan. He was an ardent lover of music, and, as a consequence, his house would be constantly filled with singing men and boys, a tribe of somewhat sinister reputation.[178] Then, when he was not engaged with music, he would be gambling in some fashion or other. After lamenting the vast amount of time he has wasted over the game of chess, he goes on: "But the play with the dice, an evil far more noxious, found its way into my house; and, after my sons had learned to play the same, my doors always stood open to dicers. I can find no excuse for this practice except the trivial one, that, what I did, I did in the hope of relieving the poverty of my children."[179] In a home of this sort, ruled by a father who was assuredly more careful of his work in the study and class-room than of his duties as paterfamilias, it is not wonderful that the two young men, Gian Battista and Aldo, should grow up into worthless profligates. It has been recorded how Cardan, during a journey to Genoa, wrote a Book of Precepts for his children,[180] a task the memory of which afterwards wrung from him a cry of despair. There never was compiled a more admirable collection of maxims; but, excellent as they were, it was not enough to write them down on paper; and the young men, if ever they took the trouble to read them, must have smiled as they called to mind the difference between their father's practices and the precepts he had composed for their guidance. Furthermore, he had written at length, in the De Consolatione, on the folly which parents for the most part display in the education of their children. "They show their affection in such foolish wise, that it would be nearer the mark to say they hate, rather than love, their offspring. They bring them up not to follow virtue, but to occupy themselves with all manner of hurtful things; not to learning, but to riot; not to the worship of God, but to foster in them the desire to drain the cup of lustful pleasure; not for the life eternal, but to the enticements of lechery."[181]

At this time Gian Battista had gained the doctorate of medicine at Pavia, and had made his contribution to medical knowledge by the publication of an insignificant tract, De cibis fœtidis non edendis. Cardan was evidently full of hope for his elder son's career, but Aldo seems to have been a trouble from the first. Yet, in casting Aldo's horoscope (probably at the time of his birth) Cardan predicts for him a flourishing future.[182] Never was there made a worse essay in prophecy. Aldo's childhood had been a sickly one. He had well-nigh died of convulsions, and later on he had been troubled with dysentery, abscesses of the brain, and a fever which lasted six months. Moreover, he could not walk till he was three years old. With a weakly body, his nature seems to have put forth all sorts of untoward growths. There is a story which Naudé brings forward as part of his indictment against Cardan, that the father being irritated beyond endurance by some ill conduct of his younger son during supper, cut off his ear by way of punishment. It was a most barbarous act; one going far beyond the range of any tradition of the early patria potestas, which may have yet lingered in Italy; and scarcely calculated to bring about reformation in the youth thus punished. In any case, Aldo went on from bad to worse; at one time his father found it necessary to place him under restraint, and the last record of him is that one in Cardan's testament, by which he was disinherited.

Gian Battista's failings were doubtless grave and numerous, but he had at least sufficient industry to qualify himself as a physician. He was certainly his father's favourite child, and on this account the eulogies written of him in those dark hours when Cardan's reason was reeling under the accumulated blows of private grief and public disgrace, must be accepted with caution. There is no evidence to show he was in intellect anything like the budding genius his father deemed him; as to conduct and manner of life, his carriage was exactly what the majority of youths, brought up in a similar fashion, would have adopted. There must have been something in the young man's humours which from the first made his father apprehensive as to the future, for Cardan soon came to see that an early marriage would be the surest safeguard for Gian Battista's future. With his mind bent on this scheme, he pointed out to his son various damsels of suitable station, any one of whom he would be ready to welcome into his family, but Gian Battista always found some excuse for declining matrimony. He declared that he was too closely engaged with his work; and, over and beyond this, it would not be seemly to bring home a bride into a house like their own, full of young men, for Cardan, as usual, had several pupils living with him. It was at the end of 1557 that the first forebodings of misfortune appeared. To Cardan, according to custom, they came in the form of a portent, for he records how he lay awake at midnight on December 20, and was suddenly conscious that his bed was shaking. He at once attributed this to a shock of an earthquake, and in the morning he demanded of the servant, Simone Sosia, who occupied the truckle bed in the room, whether he had felt the same. Simone replied that he had, whereupon Cardan, as soon as he arose, went to the piazza and asked of divers persons he met there, whether they had also been disturbed, but no one had felt anything of the shock he alluded to. He went home, and while the family were at table, a messenger, sent, as he afterwards records, by a certain woman of the town,[183] entered the room, and told him that his son was going to be married immediately after breakfast. Cardan asked who the bride might be, but the messenger said he knew not, and departed. It is not quite clear whether Gian Battista was present or not, but as soon as ever the messenger had departed, Cardan let loose an indignant outburst over his son's misconduct, reproaching him with undutiful secresy, and setting forth how he had introduced to him four young ladies of good family, of whom two were certainly enamoured of him. Any one of the four would have been acceptable as a daughter-in-law, but he declared that now he would insist upon having full information as to the antecedents of any other bride his son might have selected, before admitting her to the shelter of his roof. Over and over again had he counselled Gian Battista that he must on no account marry in haste, or without his advice, or without making sure that his income would be sufficient to support the responsibilities of the married state; rather than this should happen, he would willingly allow the young man to keep a mistress in the house for the sake of offspring, for he desired beyond all else to rear grandchildren from Gian Battista, because he nursed the belief that, as the son resembled his grandfather Fazio, so the son's children would resemble their grandfather—himself. When he was questioned, Gian Battista declared he knew nothing about the report, and was fully as astonished as his father; but two days later Gian Battista's own servant came to the house, and announced that his master had been married that same morning,[184] but that he knew not the name of the bride. Cardan now ascertained that Gian Battista's disinclination for matrimony had arisen from the fact that he had been amusing himself with a girl who was nothing else than an attractive and finely-dressed harlot, named Brandonia Seroni, the last woman in all Milan whom he could with decency receive into his house. And the pitiful story was not yet complete. In marrying her the foolish youth had burdened himself with her mother, two or more sisters, and three brothers, the last-named being rough fellows without any calling but that of common soldiers. The character of the girl herself may be judged by the answer given by her father Evangelista Seroni to Cardan during the subsequent trial. When Seroni was asked whether he had given his daughter as a virgin in marriage, he answered frankly in the negative.

Cardan at once made up his mind to shut his door upon the newly-married pair; but the unconquerable tenderness he felt for Gian Battista urged him on to send to the young man all the ready money he had saved. After two years of married life, two children, a boy and a girl, were born: husband and wife alike were in ill health, and every day brought its domestic quarrel. In the meantime sinister whispers were heard, set going in the first instance by the mother and sister of Brandonia, that Gian Battista was the father neither of the first nor of the second child. They even went so far as to designate the men to whom they rightly belonged, and contrived that this rumour should come to the ears of the injured husband. The consequence of their malignant tale-bearing was a quarrel more violent than ever, and the rise of a resolution in Gian Battista's mind to rid himself at all hazard of the accursed burden he had bound upon his shoulders.

Until the end of 1559 Cardan continued to live in Milan, vexed no doubt by the ever-present spectacle of the wretched case into which his beloved son had fallen. He records how the young wife, unknown to her husband, handed over to her father the wedding-ring which he (Cardan) had given to his son, along with a piece of silken stuff, in order to pledge them for money. This outrage, joined to the certain conviction that his wife was false to him, proved a provocation beyond the limits of Gian Battista's patience, and finally incited him to make a criminal attempt upon Brandonia's life. Hitherto he had been earnest enough in his desire to rid himself of his wife so long as she raged against him; but, on the restoration of peace, his anger against her would vanish. Now he had lost all patience; he laid his plans advisedly, and set to work to execute them by enlisting the cooperation of the servant who had been with him ever since his marriage, and by taking to live with him in his own house Seroni, his wife, and son and daughter.[185] It cannot be said that the would-be murderer displayed at this juncture any of the traditional Italian craft in setting about his deadly task. The day before the attempt was made he took out of pawn the goods which Evangelista Seroni had pledged, and promised his servant a gift of clothes and money if he would compass the death of Brandonia, who was still ailing from the effects of her second confinement. To this suggestion the servant, who had also warned Gian Battista of his wife's misconduct, at once assented.

But even on the very day when he had fully determined to make his essay in murder he vacillated again and again, and it seemed likely that Brandonia would once more be reprieved. When he entered her bed-chamber, full of his resolve to strike for freedom, he found her lying gravely ill with an attack of fever, shivering violently, and cold at the extremities. His anger forthwith vanished, and his hand was stayed; but as if urged on by ruthless fate, the mother-in-law, and the sister, and Brandonia herself, ill as she was, attacked Gian Battista with the foulest abuse and reproaches; this was the last straw. He went out and sought his servant, and told the fellow at once to make a cake and put a poison therein. The date of this fatal action was some day early in 1560.

On October 1, 1559, Cardan had left Milan, and gone back to Pavia to resume his work as professor, taking Aldo with him. He threw himself into the discharge of his office and the life of the city with his customary ardour. Over and above his work of teaching he completed his treatise De Secretis, and likewise found time to hold a long disputation on the decisions of Galen with Andrea Camutio, one of the most illustrious physicians of the age. Concerning this episode he writes: "In disputation I showed myself so keen of wit that all men marvelled at the instances I brought forward, but for a long time no one ventured to put me to the proof. Thus I escaped the trouble of any such undertaking until two accidents both unforeseen involved me therein. At Pavia, Branda Porro, my whilom teacher in Philosophy, interrupted me one day when I was disputing with Camutio[186] on some matter of Philosophy, for, as I have said before, my colleagues were wont to lead me on to argue in philosophy because they were well assured that it would be vain to try to get the better of me in Medicine. Now Branda began by advancing Aristotle as an authority, whereupon I, when he brought out his citation, said, 'Take care, you have left out the "non" which should stand after "album."' Then Branda contradicted me, and I, spitting out the phlegm with which I am often troubled, told him quietly that he was in the wrong. He sent for the Codex in great rage, and when it was brought I asked that it might be given to me. I then read out the words just as they stood; but he, as if he suspected that I was reading falsely, snatched the volume out of my hands, and declared that I was puting a cheat upon my hearers. When he came to the word in dispute he held his tongue forthwith, and all the others looked at me in amazement."[187]

It is certain that Cardan was still vexed in mind by the trouble he had left behind him at Milan. If he had not forgiven Gian Battista, he was full of kindly thought of him. He sent him from Pavia a new silk cloak, such as physicians wear, so that he might make a better show in his calling, and doubtless continued his supplies of money. Just a week before the quarrel last recorded, Aldo, against his father's wish, left Pavia and returned to Milan. Cardan used every argument he could bring forward to keep his younger son with him, but in vain; and, as he was unwilling to put constraint upon him, Aldo departed. Cardan says that he was within an ace of going with him, for the University was then in vacation: then the crowning catastrophe might have been averted, but the same fate which was driving on the son to destruction, kept the father at Pavia. Thus it happened that Aldo was an inmate of his brother's house when the poisoned cake was made. Cardan has written down a detailed account of the perpetration of this squalid tragedy, and no clearer presentation can be given than the one which his own words supply.

He writes: "Thus my son and the servant went together to make the cake, and the servant put therein secretly some of the poison which had been given him. After the cake had been made, a small piece was given to my son's wife, who was very ill at the time, but her stomach rejected it at once. Her mother ate some of it, and likewise vomited after taking it. Though Gian Battista saw what happened he did not believe that the cake was really poisoned, for two reasons. First, because he had not, in truth, ordered that the poison should be mixed therewith; and second, because his brother-in-law (Bartolomeo Sacco) had said to him, before the cake was finished, 'See that you make it big enough, for I also am minded to taste it.' Next he gave some to his father-in-law, who straightway vomited, and complained of a pricking of the tongue. He warned my son; but he, still holding that the cake was harmless, ate thereof somewhat greedily; and, after having been sick, had to lie by for some time. On the second day after this Gian Battista, and his brother, and the servant as well were taken in hold: and on the Sunday following I, having been informed of what had happened, went to Milan in great anxiety as to what I should do."