332b). Though in practice Machiavelli deviates away from this idea, it is not to say that he has rejected justice outright. It would seem that to Machiavelli, justice is a duty owed to the republic more strongly than a duty owed to another person (D III.36.292). Consequently, injustice could be the consideration of one's actions that might be construed to be against the republic. Formalities of law and practice would amount to the formation of an ethical standard which Machiavelli strives to meet by actively encouraging the condemnation of those who have broken the public trust (D I.45.93). Reasonable people can conclude that there is no justice in a world without a corresponding injustice and Machiavelli sees the injustices committed by those breaching the public's faith as among the most serious forms of injustice an individual can commit because those injustices don't seek to attain what he perceives as the common good. .
Machiavelli consistently describes injustice and ingratitude in light of suspicions, of both princes and the people. As the Discourses progresses, Machiavelli progresses his understanding of injustice and ingratitude as not only an offensive tactic for preserving the republic, but also a defensive one that can help protect the republic in the face of unexpected troubles. Every republic serves two vital purposes in Machiavelli's eyes: (1) exist freely in a perpetual state of being, and (2) be able and willing to acquire great amounts (D I.29.66). He goes on to explain that in the process of maintaining a free republic, leaders are always faced with the risk of offending citizens it should be rewarding and being suspicious of those it should find confidence in. At this point, Machiavelli begins to detail how ingratitude can lead to great evils in a republic that is corrupt while preserving great goods in an uncorrupt republic. Ingratitude stemming from suspicion often causes a corrupt republic to come "all the sooner to tyranny," as was the case with the Rome of Caesar who "took by force what ingratitude denied him" (D I.