Derrida and Lacan. Two Frenchmen, two Jacques, with two major interpreters cum 'successors': John Caputo and Slavoj Žižek (who's also a big fan of Hegelian dialectics). Two pairs, both masters of deconstruction and dialectical psycho-analysis, respectively.
Deconstruction: Destabilising meaning completely due to the infinite play of traces and the flux of power structures in community. Dialectical Psycho-Analysis: Stripping bare meaning to expose the paradoxical motives, intentions and desires behind every text, worldview and community ("the unreconciled is real; the real is unreconciled", Caputo's own description of Zizek's views, see his review of one of the latter's latest books).
One says that meaning cannot escape the constraints of the text; another says that the true meaning of any text is that which distorts its meaning.
One exposes the oppression in perspectives; another shows how the Oppressor needs the oppressed (without knowing the need). One shows how concepts have their genesis in antagonism; another exposes how antagonism is at the very core of all concepts. One seeks to destabilise the status quo; another demonstrates the inherent instability in all systems residing in that which the system believes is its most stable element.
One demonstrates how Good and Evil are social constructions; another concludes that Good and Evil are equal because Good needs Evil. One is always seeking the elusive in-deconstructible 'Justice' (beyond the horizons of textual meaning) but despairs that should we reach this it would only prove that we haven't; another declares that Justice is the unconscious striving for its Opposite, that we can only obtain perfect Justice through the worst injustices (and when we've reached it we would've only arrived at the beginning).
One aims to deconstruct knowledge; another focuses on the knowledge that other people know what we are up to.
One's hard to grasp; the other's, frankly, impossible.