ABSTRACT
The sign K (ξ) denotes a complex idea, or series of ideas, in its most simple and uncomplicated form. Its most extended form suffers from requiring the whole of psycho-analysis, past, present and future, for its expression and elucidation. Its most economical formulation is incomprehensible without experience. In this way it is analogous to mathematical signs such as, d x 2 = Σ i : j = 1 4 G i j d x i d x j https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429472558/a7fabaa8-87eb-495b-92cd-2dbcafdc44df/content/math1.tif"/> to represent a four-dimensional world of three space coordinates, and a fourth coordinate denoting time.
