Sometimes there are questions where someone asks
Is this thing that I just described possible/plausible/credible?
For example: No hunger cry from birth, is it plausible?
The big problem for questions like this is that the answer is often one big rhetorical shrug along the lines of...
Yeah, sure, why wouldn't it be?
This is rather unsatisfactory and leaves the questioner hanging.
Ask the complement question
Most often questions like these are a case where it is easier to find out if it is not possible/plausible/credible; where the complement is easier to suss than the original.
- The complement of "possible" is "impossible".
- The complement of "plausible" is "implausible".
- The complement of "credible" is "incredible"
Hence when someone asks: "Is this possible", ask yourself or the poster "Is it impossible?". If the answer to the complement-question is "No, this is not impossible", then the answer to the original question is "Yes, it is possible".
If however there are any showstoppers, that does make the thing in question impossible (there rarely are), say what these showstoppers are, so that the author can work around them.
Same with "Is this implausible?" If no, congrats, the concept works. If "yes", for what reason is it implausible?
Same with "Is this incredible?". If no, proceed with the writing. If yes, explain why this will put a strain on their reader's Willing Suspension of Disbelief.