“We become builders by building and we become just by doing what is just.”…

Concept: A character virtue is a stable disposition to choose and act well. Aristotle’s learning-by-doing principle says that such dispositions are formed through repeated corresponding actions, much as practical skills are acquired through practice.

Application: The quotation compares becoming a builder through building with becoming just through just actions. It presents both craft and virtue as capacities formed through corresponding practice, while preserving the ethical character of justice.

• “Man is a virtuous being” treats virtue as a possible state of character in the human moral agent and does not reduce it to technical production.

• “Virtues are like skill” captures the analogy that both dispositions and crafts are developed by repeatedly performing the relevant activity.

• “Skills are acquired by performing relevant activity” restates the builder side of the learning-by-doing analogy.

• “Virtue is a mechanical and non-ethical skill” collapses moral character into a production technique, even though justice concerns ethical choice and action.

Cross-check: The quotation uses building only as an analogy for how a disposition is acquired; it does not redefine justice as a mechanical craft. Therefore the assertion incompatible with the analogy is “Virtue is a mechanical and non-ethical skill.”