What is Ishmael describing when he states, "…whenever I find myself involuntarily pausing before coffin warehouses, and bringing
up the rear of every funeral I meet; and especially whenever my hypos get such an upper hand of me, that it requires a strong moral principle to prevent me from deliberately stepping into the street…"?
With these lines, Ishmael is describing the perception of human mortality and all that it represents.
We can arrive at this answer because:
Ishmael is showing how the notion of mortality prevents him from doing what he feels like when he attends a funeral.
That's because when he stops in front of coffin warehouses or realizes he's in the back of a funeral, he recognizes how fleeting human life is.
This sense of recognition of his mortality shows Ishmael that one day, he will be inside the coffin.
This prevents him from being disrespectful and acting as he pleases at funerals, as she does not want to be disrespected on the day of his death.
In this case, the notion of mortality is presented imposingly in the lines presented above. This makes the reader understand that the concept of death will be very important in the story.
