Leonardo’s advice distinguishes between how criticism and praise should be delivered within a friendship. Correction is best offered privately, where a friend can consider it without the added pressure or embarrassment of a public audience. Praise, by contrast, can be given openly because it recognises good qualities or actions without exposing the person to humiliation.

The remark reflects a broader principle of respectful communication. Criticism may be necessary, but its purpose is better served when it preserves dignity and focuses attention on the issue itself. Public criticism can easily become a display of superiority or cause defensiveness, while private discussion creates more room for honesty and reflection.

The quote can be applied to friendships, workplaces and other close relationships. It encourages people to combine candour with discretion: address faults directly but privately, while being willing to acknowledge another person’s merits in front of others.