When someone in the first minute of a debate says: "That's a nice idea, but it simply cannot be done." Is this a fallacy? If so, which one?

I think it probably is a fallacy because we should first discuss whether something is desirable and then we can brainstorm about how to get to the desired result. So the debate is in a way hijacked.

But I can't really figure out which fallacy is involved. Perhaps it has something to do with these fallacies?

  • Jumping to conclusions
  • Shifting burden of proof

But I am not entirely sure! Any input is appreciated.

  • Argument from personal incredulity? (Unless, of course, they can prove that "it simply cannot be done".)
    – cHao
    Aug 24, 2017 at 22:11

2 Answers 2


I believe it's simply a case of a false premise; They are saying "This is impossible, it's a waste of time to discuss impossible solutions, therefore we should not discuss this"

It's a perfectly valid argument (so no 'fallacy' per se) they're simply basing this argument on false assumptions.

  • Yes, but it is more than that: the false premise is used to try to kill the discussion before it has started. Maybe it is not a fallacy but at least a nasty discussion-trick... Perhaps it is indeed a form of jumping to conclusions. Oct 15, 2017 at 21:27
  • Read the concept of fallacy. "It can't be done" is a false premise. "It can't be done because it is impossible" is a fallacy.
    – RodolfoAP
    Nov 15, 2017 at 4:36
  • "It can't be done because it is impossible" is a tautology, the exact opposite of a fallacy!
    – JeffUK
    Nov 15, 2017 at 9:25
  • Read the concept of tautology. The opposite, in any case, is an oxymoron. Being a tautology does not exclude it from being a fallacy.
    – RodolfoAP
    Nov 16, 2017 at 2:08
  • Read the concept of tautology. I have,. this is a very condescending way to say you disagree with my definition, please provide your own definition if you think I'm wrong.
    – JeffUK
    Nov 16, 2017 at 12:52

Well, in order for this to be fallacy there would have to be some kind of misdirection. Like, say, the speaker of "that's a nice idea, but it simply cannot be done" could be ridiculing you or somehow trying to shift the direction.

However, this could be a polite, assertive statement. From the context, it sounds like the person had already listened to the original idea to be able to react this way.

So, I would focus more attention on

  • whether the speaker could have so much more knowledge as to be able to swiftly assess the situation (return of investment = its possible, but not feasible. That could be considered a fallacy on his part).
  • whether the speaker could be close-minded (in that case calling him on the problem wouldn't help), but trying to shift the speaker's perspective with a better solution might.
  • encouraging the speaker to express more details about why it isn't possible or what his/her concerns are.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .