The question motivating the present work is: what is really the significance of Frege with respect to the philosophical tradition? Of course this question may also be viewed as a particular case of the more general one: what is the significance of modern "Grundlagenforschung" or modern logic with respect to the philosophical tradition? The problem is of the type quid sit rather than of the type an sit, the latter enjoying nowadays an unanimously affirmative answer. Our aim is therefore to provide more precise answers to the question regarding the nature of Frege's relations with the philosophical tradition. Such relations may be considered under different aspects. In one of these aspects Frege's significance with respect to the philosophical past has already been largely dealt with; this is his purely formal logical creation. And perhaps the above mentioned unanimity is mostly restricted to Frege qua logician.