No internal inconsistencies in your information, for one thing -- as these are often signs of omitted data.
The data you have is not blindly accepted from authority without some sort of reality check.
The data aligns with new information in the area of interest as it is acquired.
The sequences make sense -- the flow of events in time is understandable and consistent with what you know about how things work.
These are a few obviosu checkpoints. People using these often just call it "intuition" but it boils down to some sort of clanging collision of illogical data at some level or other.