His ignorance was as remarkable as his knowledge.
-- Watson as Narrator (Part 1, Chapter 2)

Importance: Watson's early observation of Sherlock Holmes reveals that Holmes was a paradox. On the one hand, he was knowledgeable about certain subjects and perhaps even a genius. However, on the other hand, he lacked some common knowledge, such as knowing that the earth revolves around the sun.

The writer claimed by a momentary expression, a twitch of a muscle or a glance of an eye, to fathom a man's inmost thoughts. Deceit, according to him, was an impossibility in the case of one trained in observation and analysis.
-- Watson as Narrator (Part 1, Chapter 2)

Importance: The narrator read an article that he later found out was written by Sherlock Holmes. This quotation demonstrates the power of close observation and attention to detail. By paying close attention to detail, a person could even understand a person's secret thoughts. This quotation reveals why Holmes is so successful; he is able to...