The KISS principle could still be said to hold for biological systems, and for physical systems in a broader sense.

Inorganic and organic components are in constant flux, --aggregate/grow, break/mutate, fuse/recombine, decompose/die, recompose/create over and over. Over time the stable constellations and processes dominate, and the fragile break and gets recycleced.

To some degree it is the same with software. One of the most succesful ecosystems was and is Unix, to a large degree because of its clean design principles -- its kernel and shells structure and its proces & IPC model (I/O redirect, pipes, filters). The unix design is KISS, simple building blocks and interfaces. (and that shows in Perl too)

The periodic system and DNA are relatively simple component toolkits too, when we look at the interfaces. The way to combine these bricks though are virtually endless, and even though the basic processes of (chemical and biological) attraction/repulsion, combination/selection are are simple too, the resulting combinatorial universe and thus complex systems are mind blowing, -- given enough time to evolve. From a cloud of Hydrogen to Mozart.

We don't build software that way, yet. It will probably require the next generation of massively parallel computers combined with facilities to automatic program mutation (refactoring) and selection. And to master that kind of complexity will require an even stronger KISS focus on interfaces and basic processes than today.
-- allan

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As the eternal tranquility of Truth reveals itself to us, this very place is the Land of Lotuses

-- Hakuin Ekaku Zenji