On epistemology, rationalism, and justified true belief
Sam is in the kitchen about to wash dishes. Before starting, Sam places the wedding ring next to the sink. The doorbell rings and Sam leaves the kitchen to see who’s at the door. While absent from the kitchen, a thief opens the window directly above the sink, reaches in, and steals the ring, replacing it with a duplicate that looks and feels exactly like the original. Sam comes back in the kitchen, finishes the dishes, and puts the ring on. Sam believes it’s his/her ring.
But does Sam know it’s her/his ring?