  Notice that conclusion 6 is [\(a\cdot v ]: B\),  and not \(u : B\) ; epistemic closure holds. By reasoning in justification logic it was concluded that  [\(a\cdot v ]: B\) is a case of knowledge, i.e., ‘I know \(B\) for reason  \(a\cdot v\)’. The fact that  \(u : B\) is not a case of knowledge does not spoil the  closure principle, since the latter claims knowledge specifically for [\(a\cdot v ]: B\). Hence after observing a red  façade, I indeed know \(B\), but this knowledge has  nothing to do with 1, which remains a case of belief rather than of  knowledge. The justification logic formalization represents the  situation fairly.