In the execution of conspiracies, therefore, errors and mishaps arise from a failure of prudence or courage to which all are subject, when, losing self-control, they are led in their bewilderment to do and say what they ought not.  That men are thus confounded, and thrown off their balance, could not be better shown than in the words of Titus Livius, where he describes the behaviour of Alasamenes the Etolian, at the time when he resolved on the death of Nabis the Spartan, of whom I have spoken before.  For when the time to act came, and he had disclosed to his followers what they had to do, Livius represents him as “collecting his thoughts which had grown confused by dwelling on so desperate an enterprise.”  For it is impossible for any one, though of the most steadfast temper and used to the sight of death and to handle deadly weapons, not to be perturbed at such a moment.  For which reason we should on such occasions choose for our tools those who have had experience in similar affairs, and trust no others though reputed of the truest courage.  For in these grave undertakings, no one who is without such experience, however bold and resolute, is to be trusted.

The confusion of which I speak may either cause you to drop your weapon from your hand, or to use words which will have the same results.  Quintianus being commanded by Lucilla, sister of Commodus, to slay him, lay in wait for him at the entrance of the amphitheatre, and rushing upon him with a drawn dagger, cried out, “The senate sends you this;” which words caused him to be seized before his blow descended.  In like manner Messer Antonio of Volterra, who as we have elsewhere seen was told off to kill Lorenzo de’ Medici, exclaimed as he approached him, “Ah traitor!” and this exclamation proved the salvation of Lorenzo and the ruin of that conspiracy.

For the reasons now given, a conspiracy against a single ruler may readily break down in its execution; but a conspiracy against two rulers is not only difficult, but so hazardous that its success is almost hopeless.  For to effect like actions, at the same time, in different places, is well-nigh impossible; nor can they be effected at different times, if you would not have one counteract another.  So that if conspiracy against a single ruler be imprudent and dangerous, to conspire against two, is in the last degree fool-hardy and desperate.  And were it not for the respect in which I hold the historian, I could not credit as possible what Herodian relates of Plautianus, namely, that he committed to the centurion Saturninus the task of slaying single-handed both Severus and Caracalla, they dwelling in different places; for the thing is so opposed to reason that on no other authority could I be induced to accept it as true.