Prior to this century many philosophers, particularly those with an empiricist orientation,
attempted to justify our knowledge of general laws and theories on the basis of an inductive inference
starting from premisses which were "observation statements," presumed to be known to be true (i.e. "verified") directly by observation. By such an alleged inductive inference from particular observation statements to general statements of a theory, (i.e., "laws"), it was claimed that the truth of the univeral law was proved to follow from the presumably unproblematic truth of the allegedly directly verifiable particular observation statements. In traditional Western theories of knowledge, such proof, which would establish the necessity of the truth of the belief expressed by the conclusion of the inductive inference, was required to make that belief genuine "knowledge."
However, the inductivist picture of scientific method faced two devastating difficulties:
a) "Hume's problem" or "the problem of induction".
b) The "theory-ladeness" of observation