Theorem P(A∣B)=P(A)×P(B)P(B∣A) Robust Version P(Aj∣B)=∑i=1nP(B∣Ai)P(Ai)P(B∣Aj)P(Aj) Single Partition P(A∣B)=P(B∣A)P(A)+P(B∣Ac)P(Ac)P(B∣A)P(A)