To possess a telescope without its other essential half, the microscope, seems to me a symbol of the darkest incomprehension. The task of the right eye is to peer into the telescope, while the left eye peers into the microscope.

–Leonora Harrington, Down Below, 2017

Biology is replete with rich empirical descriptions of microscale (individual level) interactions for a wide range of systems from molecular to societal. Although many models and simulations like Conway's Game of Life elegantly show complexity can arise from simplicity, the empirically grounded microscopic descriptions we now have for biological and social systems suggest complexity begets complexity. Cells, whole organisms, and cities are more similar in complexity than textbook diagrams suggest and, although complexity might increase in a Russian doll sense as we move up organizational levels, it is not at all clear that complexity increases in any other sense—new solutions are computed and new stuff is produced but old stuff is also jettisoned or ignored. In this talk I sketch the beginnings of a new theory of emergence—The Hourglass Theory—in which there is indeed a role for simplicity but not quite the one typically ascribed to it. Rather simplicity and novelty result as adaptive systems coarse-grain microscale complexity to reduce uncertainty and use these sometimes-accurate-sometimes-error-prone perceived regularities to tune behavior.

This content is only available as a PDF.
This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. For a full description of the license, please visit