A heuristic argument is an argument that reasons from the value of a method or principle that has been shown by experimental (especially trial-and-error) investigation to be a useful aid in learning, discovery and problem-solving. A widely used and important example of a heuristic argument is occam's razor.
... Museum[?], St. Ives, Cornwall
Penlee House, Penzance[?]
Tate St. Ives[?]
Cumbria
Abbot Hall Art Gallery[?], Kendal[?]
Beatrix Potter Gallery[?], ...