Experience as boundary conditions for belief

It is not often that one uses field theory as a metaphor to clarify results from another domain; Quine manages that in Two Dogmas of Empiricism. After discussing the difficulties of defining analyticity and its relation to redutionism he opens section VI by the following image:

The totality of our so-called knowledge or beliefs, from the most casual matters of geography and history to the profoundest laws of atomic physics or even of pure mathematics and logic, is a man-made fabric which impinges on experience only along the edges. Or, to change the figure, total science is like a field of force whose boundary conditions are experience. A conflict with experience at the periphery occasions readjustments in the interior of the field.

Our knowledge is not a one-to-one representation of the world, like a full-scale map unfolded over the territory (see also Borges and Eco on this point.) The two are rather autonomous domains that only meet at the boundary, each with its own "structure".