But what is artless for Polypthon is studied by his companion in terms of art: "the Field is _formed_ by that Semi-circle of Trees into a very grand Theatre" (p. 15, _my italics_), and his eye registers an architectural feature--Vanbrugh's Pyramid--as the apt centre of that field of vision. This particular exchange at the Rotunda suggests that the usual modern discussion of landscape gardens in terms of their diminishing formality or escalating informality is less Gilpin's concern than the mind's involvement with the various landscapes. Callophilus and Polypthon can apparently both contemplate the same scene from the Rotunda, southwest towards Kent's Temple of Venus and Vanbrugh's Pyramid, yet adjudge its artifice differently. What is evidently at work in Gilpin's record of this garden is the mental experience of it, and in his case the ambiguities of his visual response.
The complicated geometry that began on Bridgeman's drawing board[6] and then was transferred to shape the grounds is certainly a survival of the old-fashioned French style in gardens. Its presence is registered by Gilpin, who allows Callophilus to note how the Gibbs building, like many other objects at Stowe designed to be seen along a variety of axes, "has its Use ... in several Prospects" (p. 8). But the psychology of the viewer has at least equal weight in Gilpin with the many-faceted object viewed from different positions.[7] And in those circumstances the presence of formal or informal designs upon the ground or the drawing-board matters less than the variety of objects and scenes within a garden and even, as at the Rotunda, the variety of viewpoint and interpretation within one vista.
Variety had, of course, always been essential to the English garden and is a special feature of Stowe, as Pope implies in the _Epistle to Burlington_ and as the writer of the appendix to Defoe's Tour of 1742 explicitly stated.[8] What we have in Gilpin's _Dialogue_ is both valuable evidence of response to garden structures, the visitor's rather than the designer's or client's account, and some hints of how the idea of variety, itself a painterly term, presented itself to Gilpin in the days before his picturesque tours.