This quote suggests that people who over-refine themselves, or go to extreme lengths to appear sophisticated, cultured, or refined, can often come across as the most vulgar. In other words, the overemphasis on refinement and sophistication can result in a lack of authenticity, which can be perceived as distasteful or vulgar. It’s a paradoxical statement that highlights the irony of refinement becoming a form of vulgarity when it’s overdone.

The term ‘vulgar’ typically refers to something lacking good taste or sophistication. However, Twain uses it here to describe those who excessively strive for sophistication, suggesting that the extreme pursuit of refinement can lead to a lack of genuine substance, making it just as vulgar as having no refinement at all.

In today’s world, this idea can be applied in several ways. In the age of social media, for instance, individuals often present highly curated versions of themselves, which can sometimes come across as inauthentic or ‘vulgar’. This quote could serve as a reminder to maintain authenticity and not to lose oneself in the pursuit of appearing refined or perfect.

In terms of personal development, this quote could be interpreted as a caution against overemphasis on external appearances or perceived sophistication. True refinement, it suggests, comes from authentic growth and development, not from an artificial veneer of sophistication. It encourages individuals to focus on genuine self-improvement rather than merely appearing ‘refined’.