Meaning of “They ought to be illustrations not authorities, studies…”

Leaves of Grass (1855), untitled first-edition poem later known as “Song of Myself,” printed page 14 (Wikisource scan page 20). The sentence follows Whitman’s warning against taking things at second or third hand and against looking only through another person’s eyes; the reviewed locator is edition-specific.

Crime and Punishment, Part III, Chapter I, printed page 203 / Wikisource scan leaf 235, Constance Garnett translation in the scan-backed 1917 Harvard Classics Shelf of Fiction / P. F. Collier & Son edition, cross-checked against Project Gutenberg #2554. Razumihin argues that going wrong in one’s own way is better than going right in someone else’s while defending the role of making one’s own errors in reaching truth; it remains energetic fictional character dialogue rather than direct Dostoevsky autobiography.

Lectures on Art, Lecture VII, Project Gutenberg #19164. The surrounding passage explicitly distinguishes learning from past masters from adopting their results as one’s own.

The Art of Literature, section “On Thinking for Oneself,” T. Bailey Saunders translation; Project Gutenberg #10714. The library analogy immediately precedes the sentence.

The Elements of Style, Chapter III, Rule 10, Project Gutenberg #37134; Strunk immediately qualifies the rule by noting legitimate uses of passive construction.

The Elements of Style, Chapter III, Rule 11, Project Gutenberg #37134; the rule concerns sentence construction, not positive-thinking philosophy.