"It's only rational."
Ok...how much data did you put in before you ran through all of the "logical" possibilities? How did you check for the things you may have failed to consider?
I don't know whether this person actually fell into this trap or not, but I know it is a trap that a lot of quite clever people fall into, & I suggest checking your brain on this from time to time.
When you are drawing "rational" conclusions, ask yourself what unverified assumptions you may have made.
