(1)　a.　A proposal α is falsifiable iff α makes a prediction that can be confirmed or disconfirmed.

What need to be added here, perhaps, is "beyond the empirical generalizations that have led to the proposal itself, " i.e., "a prediction (beyond the empirical generalizations that have led to the proposal itself)." That is to say, the proposal in question, insofar as it has an empirical content to it, must have been advanced on the basis of a (set of) generalization(s). The claim that the generalization(s) in question is/are valid, by itself, does not make a prediction, however. We make a prediction only if (i) the generalization(s) in question (call this/them G1) is/are stated in terms of theoretical concepts, and (ii) some other generalization(s) (call this/them G2) is/are stated (at least in part) in terms of the same concepts, so that clear correlations between G1 and G2 are deduced from the theoretical statements under discussion.