Aristotle's Virtues
I'm just confused if in generally the vice of deficiency means the "definicency of the mean" OR the deficiency of what is stated.
Ex: cowardice the definicency of courage
OR
deficiency of cowardice: being lack of cowardice
From your example, cowardice is the lack of courage.
deficiency = lack
In Aristotle's virtue ethics, the vice of deficiency refers to the lack or insufficiency of a particular virtue, which he calls the mean. The mean represents a moderate point between excess and deficiency.
Using your example, let's consider the virtue of courage. Aristotle would say that cowardice is the vice of deficiency in relation to courage. Cowardice is the state of being excessively fearful or lacking the necessary bravery and courage. It falls short of the mean of courage, which is the desirable balance between recklessness (excess) and cowardice (deficiency).
So, to clarify, the vice of deficiency is the deficiency of the virtue itself, not the deficiency of what is stated. In the case of courage, the deficiency is in the lack of courage, which is cowardice.