Observation of a fact sometimes demands for an explanation. This explanation cannot take place in a vacuum. It requires a framework under which the process of explanation is to be carried out. A framework can be regarded as some set of assumptions and mode of enquiry.
It is possible to build a body of knowledge whose parts are coherent with each other under that particular framework, yet it doesn't guarantee the correspondence between the assumptions held under which the act of explanation was  carried out and the external reality outside the assumption.
The enquiry sometimes during the process of explanation may encounter something which goes against the basic assumption under which the initial act of explanation begun leading to this Paradox.
Of all the frameworks I have known so far only SCIENCE reexamins it's assumotion, sometimes leading to the complete abandonment  of the old ones  and devising a new set of them.

This second order assumption isnpite of it being able to explain the paradox, the gap of  correspondence between these newly devised assumptions and the external reality still remains open.

Now depending upon one's understanding of knowledge one can become an agnostics, a skeptic, a nihilistic or a pragmatic.
The scientific rigour demands one to be a pragmatist during such instances. Knowledge, according to science, is not a mean to reach the ultimate, it's only a survival tool.