"You generally hear that what a man doesn't know doesn't hurt him, but in business what a man doesn't know does hurt"
About this Quote
The intent is practical, but the subtext is moral. Business, in this formulation, is a domain where ignorance isn’t innocence; it’s liability. Not knowing the terms, the risks, the incentives, the fine print - these aren’t abstract gaps in knowledge, they’re openings for loss, exploitation, or self-deception. Brenan’s phrasing also carries a quiet cynicism about how “business” works: it’s not primarily governed by goodwill or shared assumptions, but by asymmetries of information. Someone usually knows more, and that knowledge tends to be monetized.
Context matters. Brenan lived through the churn of early 20th-century capitalism, war economies, and shifting class structures in Britain and Europe. Against that backdrop, the quote reads less like advice for entrepreneurs and more like a cultural diagnosis: modern life increasingly routes survival through systems too complex to navigate on vibes. The line works because it’s spare and adversarial - it refuses the sentimental idea that ignorance is protective, insisting instead that the world, at least the commercial one, keeps score.
Quote Details
| Topic | Business |
|---|---|
| Source | Help us find the source |
| Cite |
Citation Formats
APA Style (7th ed.)
Brenan, Gerald. (2026, January 16). You generally hear that what a man doesn't know doesn't hurt him, but in business what a man doesn't know does hurt. FixQuotes. https://fixquotes.com/quotes/you-generally-hear-that-what-a-man-doesnt-know-120552/
Chicago Style
Brenan, Gerald. "You generally hear that what a man doesn't know doesn't hurt him, but in business what a man doesn't know does hurt." FixQuotes. January 16, 2026. https://fixquotes.com/quotes/you-generally-hear-that-what-a-man-doesnt-know-120552/.
MLA Style (9th ed.)
"You generally hear that what a man doesn't know doesn't hurt him, but in business what a man doesn't know does hurt." FixQuotes, 16 Jan. 2026, https://fixquotes.com/quotes/you-generally-hear-that-what-a-man-doesnt-know-120552/. Accessed 13 Feb. 2026.














