Because the criterion attends on our activity (c.f. §84) our inquiry into it must follow the same path as our inquiry into the science it belongs too: that path of self-education already described (c.f. §77-78) whereby we attend to the activity of consciousness engaging in that inquiry.
The different moments of knowing are not only present in this consciousness as distint from one another, but moreover as presented together
to the consciousness for which they are. Neither then do we need to engage in a kind of testing procedure of one moment against the other, as if this testing were something other than the consciousness to which we are already attended. Rather, this consciousness, through its act of presenting the moments together, is already, as it were, the act of testing. When we become consciousness of a discrepancy between these moments, between the for us
and in itself
so posited, we alter in reflection our knowing in order to address this error (c.f. §79). Were the in itself
absolutely present to us from the outset as a criterion, this altering would amount to an adaptation of the for us
until we can make it match the former. But the in itself
is not so present, but rather is given as one of the moments of a knowing which now finds itself inadequate. It is this knowing per se which is altered, our conception of the in itself
as much as the for us
. Supposed object and supposed knowledge of it change together as consciousness struggles to educate itself about that which can in fact be known (c.f. §80).