What kind of criteria would make a speculative question of sorts a well-founded question? A possible rough draft would be:
- Clearly display some honest work on the question
- Question overlapping carefully enough with mainstream science
- Question having loose ends (thereby the "speculative" feature)
- Not "review-my-equations" kind of question
- (Stylistic) Narcissistic attitudes are off the table
Some rationale for these points:
R1) It mustn't be in the way of: "Here's a vague idea, can you help me fill in the details?
R2) Relation to previous working theories should be easily traced back
R3) It mustn't be a finished idea. If it's finished, it belongs in the peer-review system
R4) Nobody's here to track down your sign mistakes.
R5) Nobody's here to admire how clever you are