Men usually grow base by degrees. From me, in an instant, all virtue dropped bodily as a mantle. I shrouded my nakedness in triple guilt.

The narrator makes this comment as he begins to introduce the story, explaining that he is going to tell about the event that caused him to drop his “mantle” of virtue. Although the narrator so greatly desired the death of Wilson and hence the end of all self-restraint, his complete freedom doesn’t appear to have brought him happiness. The idea that he clothes himself in “triple guilt” could mean either that he behaves three times as guilty, that he feels three times as guilty, or perhaps most likely, both.

In truth, the ardency, the enthusiasm, and the imperiousness of my disposition soon rendered me a marked character among my schoolmates, and by slow but natural gradations, gave me an ascendency over all not greatly older than myself—over all with one single exception.

This quotation appears as the narrator describes the social aspect of his school life in Dr. Bransby’s Academy, and how he came to rise to the top of the school’s social hierarchy. Although only describing this part of his life, this quotation illuminates how the narrator thinks of himself in relation to others. He sees his social ascendancy as “natural,” inherent to his personality. For all his later regret and remorse, the narrator appears to have had a strong sense of self-importance leading to an equally strong sense of entitlement.

I had always felt aversion to my uncourtly patronymic, and its very common, if not plebeian, praenomen.

The narrator here explains his dislike for his real name at the same time as he introduces why the likeness of his doppelganger, William Wilson, upsets him so greatly. The use of elevated words such as plebeian, patronymic, and praenomen contrasts with how base and common he considers his real name to be. The narrator hates the idea that he might be ordinary or common because he sees himself as unique, intelligent, and superior to those around him. His emphasis that his last name is uncourtly further highlights that the narrator resents his lack of noble title.