Which of the following best characterizes a "stoic" individual?

A "stoic" individual is best characterized as someone who is not affected by passion or feeling. This definition aligns with the philosophical stance of Stoicism, which teaches that virtue and wisdom are the highest goods and that one should maintain a level of emotional detachment in the face of life's challenges. Stoics strive for inner peace and resilience, often advocating that external events should not disturb one's calm or dictate emotional responses.

In contrast, the other options describe traits that are in direct opposition to stoic philosophy. For instance, being highly emotional or excessively cheerful implies an attachment to external conditions that can lead to emotional turbulence, which stoicism seeks to transcend. Similarly, always being enthusiastic suggests a lack of rational control over feelings, which is not in alignment with the stoic ideal of maintaining equanimity and temperance. Hence, the correct characterization of a stoic individual emphasizes their ability to remain unaffected by emotions or passions.