On July 26, 2025, six of us continued our discussion of Daniel Dennett’s From Bacteria to Bach and Back. Dennett notes that three conditions are needed for Darwinian evolution: 1. A population must have variation in characteristics. 2. Some of those variations allow those members to survive better with a higher rate of reproduction. 3. Heredity transfers the favorable variation to the descendants. These requirements are akin to an algorithm that guides the 3D printer head, which is moved by stepper motors in three axes. Instead of printing a plastic bin for holding miscellaneous parts, a fitter species emerges.
Dennett uses Godfrey-Smith’s cube, where the sides have the value of one. In one corner of the cube, he places the origin for the Cartesian x, y, and z axes. The x-axis ranges from 0, where there is low fidelity of replication of genes, to 1, having high fidelity. The y-axis ranges from 0, where a population has no variation to 1, where there is sufficient variation. The z-axis ranges from 0 where there is no selection for a variation by a landscape, to 1 where the environment favors a variation and permits survival.
Evolution cannot take place at the origin (0,0,0) where there is low fidelity in gene replication, no variation in a population, and no changing environment to select a variation. The paragons of Darwinian evolution are at the vertex (1,1,1), where the best variation fits in a niche and is better for competing for resources. At the vertex (1,0,0) without a changing environment, there is drift in the genetic code as mutations accumulate, but there is no selection pressure for these mutations. Those variations randomly drift. At the vertices (1,1,0) the landscape is too rugged for any variation to be favored for survival. At vertices (0,1,1), there is a catastrophe of too many replication errors where genes are not properly duplicated, and variations are not passed on to descendants. At the vertices (1,0,1), we can place human cells that developed from the zygote in a maternally provided and protected space, without a Darwinian process to select them.
Using other variables for dimensions, the cube can be used to describe how life, culture and even intelligent design emerge. If the x-axis is going from persistence to reproduction, y-axis is the increasing ability to harvest energy, and the z-axis goes from simple to complex, the vertex (0,0,0) is abiotic, before life arises, and the archaea and bacteria are at the vertex (1,1,1) with sufficient complexity to give it the ability to reproduce and harvest energy. We can use the cube to compare an Australian termite mound to Gaudí’s La Sagrada Familia Basilica. The x-axis starts from "bottom-up," where design is part of the building process, to “top-down," where there is a design that can be broken into smaller steps to assemble a building. The y-axis is the level of comprehension, the ability to understand how the elements of design are put together. The z-axis starts at 0, which is essentially trial and error, random searches, to 1, where there are systematic searches. At vertex (0,0,0), there is a termite mound built with a myriad of passageways and ventilation shafts to house millions of termites and eerily shaped like La Sagrada Familia Basilica. No termite is the master architect barking out orders to build it. Instead, instinctual behavior constructs the termite mound shaped by years of natural selection, an example of competence without any comprehension, and design without a designer. On the other hand, at the vertex (1,1,1) there is an intelligent designer, Gaudí, who has comprehended the task, breaking the steps to construct, and assigning teams to oversee each detail to build a basilica where competence is shaped by comprehension.
Life was built from the bottom up. There is no master design or designer. The stuff of life is the variation selected by an environment that builds the biological entities to fit into each niche, competing for resources, and passing those variations encoded in genes to descendants. Life’s hardware and software have evolved and not been designed. Humans evolved with hardware, but with the ability to change the software. Without anthropomorphic hubris, humans are the first species with the capacity to design intelligently. How did the software develop to allow us to become designers?
We invite you to find out how we became designers in our continuing discussion of Daniel Dennett’s From Bacteria to Bach and Back: The Evolution of Minds, B105.C477D445 2017, on August 16, 2025, from 2 PM to 4 PM.
