Indeed a strong relish for physical philosophy has, I fear, tinctured my mind with a very common error of this age — I mean the habit of referring occurrences even the least susceptible of such reference, to the principles of that science.

This quotation appears toward the very beginning of the story, as the narrator describes his background. Here he establishes the transformation of his perspective over the course of the story. As he states, he was once a man who believed only what science could explain. However, this story is narrated with hindsight, and from this description, it’s clear that the narrator has since begun to doubt science’s ability to explain everything. He even goes so far as to call it an error, suggesting he regrets his previous beliefs.

‘See! see!’ — cried he, shrieking in my ears, — ‘Almighty God! see! see!’

The Old Swede here cries out upon first seeing the ghost ship break through the unending darkness. This terrifying moment of epiphany is the Old Swede’s last before he’s killed in the collision between the two ships. If we read the Old Swede as urging the narrator to see what he sees, his last moments are about proving to the narrator the supernatural quality of their doomed voyage. If we read the words as the Old Swede reporting what he sees, it ties into the theme of dangerous knowledge. The Old Swede may see but seeing changes nothing.

I shall from time to time continue this journal. It is true that I may not find an opportunity of transmitting it to the world, but I will not fail to make the endeavor. At the last moment I will enclose the MS. in a bottle and cast it within the sea.

The narrator makes this comment after spending some time on the ship and realizing that because the crew cannot see him, he is effectively alone. This quotation explains the story’s framing device, making us view all that has come before and after with fresh eyes. We now know that this story is the titular manuscript found in a bottle, and that we are reading it means that the narrator is likely dead. This revelation increases the sense of dread permeating the story.

The ship and all in it are imbued with the spirit of Eld. The crew glide to and fro like the ghosts of buried centuries, their eyes have an eager and uneasy meaning…

After failing to discern anything about the ship’s make, purpose, or crew, the narrator admits to the doubts that have been growing within him since he was first flung on board. This moment the narrator admits without equivocation that he has found himself in a situation with no logical explanation, one that science cannot help him understand. This comment marks a turning point in the narrator’s character, and his exploratory zeal begins to dim.

 It is evident that we are hurrying onwards to some exciting knowledge—some never-to-be-imparted secret whose attainment is destruction.

Trapped on the ghost ship, the narrator makes this comment as he realizes that the ship appears to be on course to somewhere. Even after admitting to the supernatural horror of his adventure, the narrator admits he’s still curious about the ship’s mysteries. However, unlike previously in the story where this curiosity might have led him to examination or observation, he only has this vague and foreboding thought. With this quotation, he articulates one of the story’s major themes, that the pursuit of knowledge can ultimately lead to danger and destruction.