As I like to put it: unit tests don't affirm the correctness of code with respect to a specification, they merely affirm that certain implications of the specif

As I like to put it: unit tests don't affirm the correctness of code with respect to a specification, they merely affirm that certain implications of the specification hold with the code under test. In that sense, the general tendency to assume correctness in the face of passing test suite is basically an instance affirming the consequent on a huge scale.