"This above all: to thine own self be true" for many people is translated into "That's just who I am." This can function as a justification for morally flawed attitudes or actions.
The modern era has given rise to an ideal of life that would have sounded very strange to the majority of philosophers, religious thinkers, and others who thought deeply about the point of life in previous centuries. Authenticity is one of the modern era's crowning virtues. But while being "true to yourself" is important, it is not always desirable.
As Jennifer Herdt points out in her book, Putting on Virtue, those who worry that they are not being authentic when they seek to practice a new virtue can become bogged down in self-reflection. This can happen in a way that "short-circuits character development" (p. 1). Authenticity can sometimes function as an excuse for ignoring or accepting flaws in our character.
Consider a person who is short-tempered and impatient with others. When a friend or co-worker attempts to discuss this with him, he might say "That's just who I am," as an expression of his commitment to being authentic, but also as a way of avoiding an honest self-examination. Such an examination might require moral change that is neither easy nor initially pleasant. Character development can be hard work, and we may use authenticity as an excuse for avoiding it.
On the positive side, authenticity requires that we not construct and display a façade of virtue. Hypocrisy in all of its forms is rightly to be avoided and condemned. However, there is the authentic self that we are, and the authentic self that we ought to be. A concern for authenticity is important, but it should be grounded in a pursuit of virtue.
Mere authenticity is the wrong aim for life. Rather, authentic virtue should be our goal.
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