The count
A symmetrical triangle needs two converging lines, each touched at least twice. An ascending triangle has a flat ceiling and a rising floor. A descending triangle has a flat floor and a falling ceiling. The flat side is the one people invent by tilting the page. We check it with a ruler.
A single swing that happens to lean inward is not a touch you can build on. We mark touches with small dots. If one side has two dots and the other has one, the sentence in the margin is incomplete, not triangle.
Where triangles go to die
Near the apex, the pattern is often already over as a useful drawing. Price that crawls into the point and then wanders has used up the structure. On the failed-pattern evening we keep a folder of these. They were triangles. Then they became noise inside the lines, and the honest act was to stop updating the boundaries every bar.
If you sketch at home, stop after four touches and write the type in the corner: symmetrical, ascending, or descending. If you cannot choose, the lines are not ready, and the Recognition Circle’s third evening is the place we practice that choice out loud.