From the last stanza of Wallace's Six Significant Landscapes:
Rationalists, wearing square hats,
Think, in square rooms,
Looking at the floor,
Looking at the ceiling.
They confine themselves
To right-angled triangles.
If they tried rhomboids,
Cones, waving lines, ellipses --
As, for example, the ellipse of the half-moon --
Rationalists would wear sombreros.
....If not sombreros, perhaps skirts worn upside down to resemble a Native American headdress.....