Finally, it is in a high degree dangerous to entrust an important negotiation to a man of irregular life whose domestic and personal habits are disorderly. How can one expect of such a man a greater degree of order and of decency in public affairs than that which he shows in his own private concerns, which ought indeed to be the constant gauge of his capacity. If he is too fond of the gaming-table, of the wine-glass, and of frivolous amusements, he is not to be entrusted with the discharge of high diplomatic duty, for he will be so unreliable that at moments when he seeks the satisfaction of his ill-regulated desires he will be prepared to sell the highest secrets of his master. [Sidenote: _The Cool Head._] A man who is naturally violent and easily carried away is ill fitted for the conduct of negotiations; it is almost impossible for him to be master of himself at those critical moments and unforeseen occasions when the command of one’s temper is of importance, especially at the acute moments of diplomatic controversy when a choleric word may poison the minds of those with whom negotiations are in progress. It is also difficult for any man who is easily irritated to remain master of his own secret; for, when his anger is aroused, he will allow words to escape him from which an adroit hearer will easily divine the essence of his thought, and thus lead to the ruin of his plans. Before his elevation to the cardinalate, Cardinal Mazarin was sent on an important mission to the Duke of Feria, Governor of Milan. He was charged to discover the true feelings of the Duke on a certain matter, and he had the cunning to inflame the Duke’s anger and thus to discover what he would never have known if the Duke himself had maintained a wise hold over his feelings. The Cardinal indeed had made himself absolute master of all the outward effects which passion usually produces, so much so that neither in his speech nor by the least change in his countenance could one discover his real thought; and this quality which he possessed in so high a degree contributed largely to make him one of the greatest negotiators of his time. [Sidenote: _Spanish and Italian Characters._]