  Both Frege and Russell (after the latter's initial flirtation  with idealism) were concerned to show, against Kant, that arithmetic  is a system of analytic and not synthetic truths. In the  Grundlagen, Frege had offered a revised conception of  analyticity, which arguably endorses and generalizes Kant's  logical as opposed to phenomenological criterion, i.e., (ANL) rather than (ANO) (see the supplementary section on   Kant):  