This quote essentially talks about the dual nature of human beings, suggesting that every person has the capacity for both virtue and vice. It implies that it is a matter of degree to which these traits are present in each individual – some may lean more towards virtue, others more towards vice, but no one is entirely one or the other. The "few in the extreme" part indicates that only a small number of people are entirely virtuous or vicious, most people fall somewhere in between.

Applying this concept to personal development, it suggests that we should strive for self-awareness, acknowledging both our strengths (virtues) and weaknesses (vices). It’s about accepting our flaws and working on them, while also nurturing and strengthening our positive traits. This balance is important for growth and self-improvement.

In the context of today’s world, this quote can be seen as a reminder that no one is perfect. It can be applied to how we judge others and ourselves. We often categorize people as good or bad based on their actions, forgetting that everyone has the capacity for both virtue and vice. It’s a call for empathy, understanding, and acceptance of human complexity.

Moreover, it could be interpreted as a commentary on the societal pressure to be perfect, to be virtuous in all aspects. This quote reminds us that it’s natural to have flaws, to err, and to have weaknesses – that’s part of being human. It’s about finding the balance and striving for improvement, not perfection.