The notions of 'meaning' and 'historicity', of the manner in winch they inform or reflect conceptions of collective or ‘social’ being and of individuality, and of the ways in which these dimensions are primordially experienced by human beings. This investigation concerns primarily the phenomenological and hermeneutic traditions and especially Heidegger’s formulation of the notion of historicity as correlative to the 'event' of truth understood in terms of an interplay between disclosure and concealment 0eia) and Gadamer's understanding of 'meaning and historicity’ (...) as an indispensable couplet for both philosophical hermeneutics and the social sciences. Nevertheless the present inquiry does not content itself with an exploration of the notions of 'meaning' and historicity' within the confines of the phenomenological-hermeneutic tradition, but rather attempts to attain a more adequate grasp of those concepts by a critical Juxtaposition of Heidegger and Gadamer with accounts that have the 'social' as their point of departure. Thus, Heidegger’s formulations on historicity are not only examined in relation to his 'immediate' legacy of German thought -especially Hegel and Nietzsche- but are also contrasted with conceptions of history pertaining to the Marxist tradition and especially Castoriadis’ conception of the social-historical. In effect, the contrast between 'historicity' and the workings of 'actual' history has arguably prevented a genuine dialogue between the Marxist and the phenomenological camps. Far from being concerned with a synthesis of those traditions or from being preoccupied with justifying either of them I have attempted to show that a combined reading of both is indispensable for the disclosure of the essential dimensions of historical experience. Castoriadis' emphasis on the ‘magmatic’ character of unconscious significations and his grounding of social-historical 'instituting' on the unconscious, together with Heidegger's attempt to link the primordial experience of history with myth have given me occasion to dissociate the very notion of 'meaning' from that of 'rationality'. This should not be interpreted as a rejection of rationality or as an -at bottom- ethical invocation of a return to a pre-Critical philosophical position but rather as an attempt to indicate the primordial manner in which history is accessible in experience and which arguably precedes any thematic theorizing of the historical realm. I have finally attempted to show the antinomies inherent in any attempt to grasp ‘rationally’ the social-historical by a detailed exploration of Gadamer's ambivalent conception of tradition’ and 'prejudice'. Gadamer’s conception of the ‘fusion of horizons’ gave me occasion to reflect further on the manner in which history and truth are made correlatively accessible in thought, in experience, and in historical praxis. (shrink)