H. P. Grice's seven-step derivation of buletic acceptability

(1) 

Fundamental law that (ceteris paribus) for any creature x (for any A, B), if x wills A and judges that if A, then A as a result of B; then x wills B. 

(2) 

x wills that (for any A, B) if x wills A and judges that if A, A as a result of B, then x is to will that B. 

(3) 

x should (qua rational) judge that (for any A, B) if it is satisfactory to will that A and also satisfactory to judge that if A, A only as a result of B, then it is satisfactory to will that B. 

(4) 

x should (qua rational) judge that (for any A, B) if it is satisfactory that ! A and also satisfactory that if ⊢A, then ⊢A only as a result of B, then it is satisfactory that ! B. 

(5) 

x should (q.r.) judge that (for any A, B) if it is satisfactory that if ⊢A, ⊢A only because B, then it is satisfactory that, if let it be that A, then let it be that B. 

(6) x should (q.r.) judge that (for any A, B) if A, A only because B, yields if let it be that A, then let it be that B. 

(7) (For any A, B) if A, A only because B yields if let it be that A, then let it be that B.