Success depends on three things: who says it, what he says, how he says it; and of these three things, what he says is the least important.

Morley’s aphorism stresses that persuasion and public success are governed less by the bare propositional content of a message than by ethos (the speaker’s standing and credibility) and delivery (tone, style, timing, and rhetorical skill). In politics, journalism, and public debate—fields Morley knew intimately—the same argument can fail or triumph depending on who advances it and how it is framed. The line also implies a skeptical view of “pure” rational deliberation: audiences are moved by authority, character, and performance as much as by reasons. Read this way, the quote is both a practical observation about rhetoric and a warning about how easily substance can be eclipsed by reputation and presentation.