Buchak (2014) argues that what partial beliefs count as full beliefs cannot merely be a matter of the degree of partial belief, but must also depend on the type of evidence it is based on. According to Buchak, this means there can be no merely formal answer to the question: what conditions on partial belief are necessary and sufficient for full belief? The following example, of a type going back to Thomson (1986), illustrates the point. Your parked car was hit by a bus in the middle of the night