Like the transcendental illusion to which he refers in Donner le temps 1, for example (DLT1, 46/GT1, 30), there is a form of reason analysed by Derrida which contravenes the formal rationality it springs from. For Kant ‘transcendental illusion’ – a kind of post-Baconian ‘Idol of the mind’ – arises when the judgment becomes detached from its positive moorings in experience, and enjoys for a while the sensation of being powered under its own steam: it suffers the ‘illusion’ that it can generate its own conditions of functioning, ‘transcendental’ in only a phoney, adventitious or delinquent way. A schema such as this is a far cry – and on several counts – from analyses offered by Derrida (much too much conflating and aligning of Derrida with varying ‘precursors’ gets accepted these days as sufficient exposition), and yet this motif of a rationality capable of going against itself, or beyond itself, makes for a powerful link in the singular, sprawling history of ideas that provides a context for the present discussion.

I wish to let this context be dominated for now however by Hegel, not Kant. For it is in Hegel especially and in Derrida's readings of him that an interested party can look for and find that spoliation of reason by something within its precincts that reveals autobiography to be perhaps the most fertile, if an unlikely, place for working on ideas of reason ‘itself’.