“They did not know it was impossible, so they did it.”
— Mark Twain · 1835 – 1910Source: no specific work is documented · Check the source
Disputed attributionWhat we know
- What is documented
- The phrase is widely circulated under Mark Twain’s name, but the available evidence cites secondary quote sites rather than any primary Twain source.
- What remains uncertain
- Attribution is disputed: no verified Twain publication or speech is provided, and the line appears in modern compilations and alternate attributions.
Understanding the quote
The line celebrates bold action: when ‘impossible’ exists mainly in people’s minds, not in facts, audacity gets results. It fits Mark Twain’s skeptical, witty voice, yet no primary Twain text in the research proves he wrote or said it.
In the original · French
Ils ne savaient pas que c'était impossible, alors ils l'ont fait.
The story behind it
Quote collections frequently list this under Twain without a single primary citation — a textbook case of attribution drift.
Going further
- The era
- Late 19th–early 20th century America, the era of Twain and industrial optimism.
- The thinking
- Practical takeaway: don’t let perceived limits stop action. Trying first and figuring things out later often beats waiting for certainty.
- Key word
- Perceived impossibility: a barrier formed by belief rather than reality.
- Who quoted it
- Popular in business and self‑help circles; occasionally misattributed to figures like Winston Churchill.
Three challenges to live it
In the app, you pick the one that fits your day, and in the evening you say how it went.
Write a 6-line micro-story where a character pulls off what everyone called impossible; keep it under 200 words.
Fiction lets you rehearse bold choices: imagining an 'impossible' success reveals practical steps and breaks assumed limits.
List 3 mini-experiments you would call 'impossible' then schedule a testable, measurable version of one this week.
Breaking a perceived impossibility into small experiments creates tangible evidence and challenges limiting beliefs from the quote.
Invite someone who says 'that's impossible' to try a scaled-down version of the challenge with you for 30 minutes today or this week.
Action together dissolves doubt: the quote suggests disbelief blocks action, so shared trying disarms assumptions and sparks possibilities.
When have you acted despite thinking something might be impossible?
Report an error
Does an attribution, a source or a translation look wrong? Tell us: every report is read, and the entry is corrected if needed.