What can the reader infer from the following paragraphs?

Throughout the passage, Holmes is attempting to explain to the narrator that the human mind is finite, and so he has to “forget” certain types of knowledge in order to preserve space in his brain for knowledge that is useful for his work. The narrator believes knowledge about the Solar System is essential, but Holmes, in this selection, reiterates to him that this knowledge would make no difference to his work and is therefore not important.