Leonardo’s statement argues that praise and blame should depend on whether a person had meaningful control over an action. Someone can reasonably be held responsible for choices they were free to make or refuse, while events outside their control should not carry the same moral judgement.

The idea connects ethical responsibility with personal agency. Fair judgement therefore requires attention to what a person could actually influence, including the choices available to them and the constraints under which they acted. Outcomes alone are not sufficient grounds for deciding whether someone deserves credit or criticism.

The principle also has relevance to legal and everyday assessments of responsibility. It encourages a distinction between deliberate conduct and circumstances that could not reasonably have been prevented. In this sense, praise and blame are presented as appropriate only where genuine choice and the capacity to act differently were present.

Alternative translation

“Man merits praise or blame solely in such matters as lie within his option to do or not to do.”