“All grids are fields, but not all fields are grids. One of the potentials of the field is to redefine the relation between figure and ground. If we think of the figure not as a demarcated object read against a stable field, but as an effect emerging from the field itself – as moments of intensity, as peaks or valley within a continuous field – than it might be possible to imagine figure and field as more closely allied. (…)”
Stan Allen on Wikipedia.