I will not deprive deceit of its due; that were but ill to understand the world:  I know it has often been of great use, and that it maintains and supplies most men’s employment.  There are vices that are lawful, as there are many actions, either good or excusable, that are not lawful in themselves.

The justice which in itself is natural and universal is otherwise and more nobly ordered than that other justice which is special, national, and constrained to the ends of government,

          “Veri juris germanaeque justitiae solidam et expressam
          effigiem nullam tenemus; umbra et imaginibus utimur;”

     ["We retain no solid and express portraiture of true right and
     germane justice; we have only the shadow and image of it.” 
     —­Cicero, De Offic., iii. 17.]

insomuch that the sage Dandamis, hearing the lives of Socrates, Pythagoras, and Diogenes read, judged them to be great men every way, excepting that they were too much subjected to the reverence of the laws, which, to second and authorise, true virtue must abate very much of its original vigour; many vicious actions are introduced, not only by their permission, but by their advice: 

     “Ex senatus consultis plebisquescitis scelera exercentur.”

     ["Crimes are committed by the decrees of the Senate and the
     popular assembly.”—­Seneca, Ep., 95.]

I follow the common phrase that distinguishes betwixt profitable and honest things, so as to call some natural actions, that are not only profitable but necessary, dishonest and foul.

But let us proceed in our examples of treachery two pretenders to the kingdom of Thrace—­[Rhescuporis and Cotys.  Tacitus, Annal., ii. 65]—­ were fallen into dispute about their title; the emperor hindered them from proceeding to blows:  but one of them, under colour of bringing things to a friendly issue by an interview, having invited his competitor to an entertainment in his own house, imprisoned and killed him.  Justice required that the Romans should have satisfaction for this offence; but there was a difficulty in obtaining it by ordinary ways; what, therefore, they could not do legitimately, without war and without danger, they resolved to do by treachery; and what they could not honestly do, they did profitably.  For which end, one Pomponius Flaccus was found to be a fit instrument.  This man, by dissembled words and assurances, having drawn the other into his toils, instead of the honour and favour he had promised him, sent him bound hand and foot to Rome.  Here one traitor betrayed another, contrary to common custom:  for they are full of mistrust, and ’tis hard to overreach them in their own art:  witness the sad experience we have lately had.—­[Montaigne here probably refers to the feigned reconciliation between Catherine de Medici and Henri, Duc de Guise, in 1588.]