Meta-epistemological territory, then, asks questions about how knowledge is possible. But insofar as epistemology carries within it a bias of the Western rational tradition it overlooks the original phenomenon of world which renders things intelligible (and thus ultimately knowable). It sees knowledge as the primary mode of access to beings, underpinning all possible activity (knowing how to ride a bike, for example, is considered a sort of unconscious knowledge as opposed to practical know-how - the distinction between propositional knowledge and practical understanding is not there). For this reason a distinction between first-order and second-order statements cannot coherently emerge, because knowing how you know is seen as the only way to get at the understanding that you know.
However, once the ontological ground has been cleared it's then possible to ask meta-epistemological questions about intelligibility, and what is given over to knowledge. For instance, Samuel Todes refines Merleau-Ponty's researches into the role of embodiment in intelligibility by pointing out that the forward-back, up-down, and other spatial "categories" delivered over to our understanding non-cognitively (i.e. prior to knowledge) enable us to understand more complex concepts (like the "forward" arrow of time, or higher and lower values). As this understanding is not first given over by knowledge but is grasped initially simply by virtue of being embodied it cannot be susceptible to the sceptic's touch. Mental content, such as propositions, are only possible on the basis of non-cognitive worlded activity. Conscious, knowing experience is not primary as knowledge is a founded mode of being-in-the-world and as such cannot make sense of itself.
Not being able to know that the world is real is not a problem as the world is in fact given along with the possibility of having representations at all. One can only pose the sceptic's question if they see themselves primarily in the mode of knowing (which is not the case) and thus owning the sentiment that you can only get at the reality of the world through knowledge itself. As we have modes of access to beings which are not propositional in character (using them, or being them as in the case of the orientation of the body) we can be sure those beings are indeed there. Accordingly, if the preceding estimations are correct (owing to Heidegger's phenomenological account) it is in fact no problem at all.
With its ontological foundations in place the region of discourse available to epistemology is clearly defined. Second-order statements about the ontological-existential possibility of knowledge are released from being appraised by the same modes of investigation as first-order epistemological questions about knowledge itself.