The uncomfortable part is that these "fields" are mathematical constructions.
While field lines are a "mere" mathematical construction, in some circumstances they take on physical significance.
Experience remains, of course, the sole criterion of the physical utility of a mathematical construction.
Then, one give rigorous mathematical constructions of examples satisfying these axioms.
A Calabi-Yau space is a mathematical construction used by physicists to describe parts of nature that are too small to see with the human eye.
There is always the hope that a mathematical construction, a product of the human imagination, nevertheless corresponds to some truth in the external world.
The sculpture has a simple mathematical construction, increasing in length and height as the piece zigzags down the slope.
They and mathematical constructions, such as Lagrangian multipliers, are given an operational economic interpretation.
There are many mathematical constructions similar to or more general than fuzzy sets.
Many scientific theories begin as more speculation than ordered logical mathematical constructions.