
“the most complete presentation of the principles of design ever made by a modern artist – it constitutes the Principia Aesthetica of a new era of art, in which Klee occupies a position comparable to Newton’s in the realm of physics.”

via Open Culture
![Richard Waller Tabula colorum physiologica … [Table of physiological colors] Philosophical Transactions of the Royal Society of London, 1686](https://library.si.edu/sites/default/files/39088018207936-1000.jpg)