Technological Evolution Biological Evolution

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1 Technological Evolution Biological Evolution SFI Technology Workshop, Aug 7, 2013 W. Brian Arthur External Professor, Santa Fe Institute and Intelligent Systems Lab, PARC

2 A question: Can there be a theory of evolution for technology? 2013 W. Brian Arthur 2

3 Evolution s two meanings: Lineages alter their form descent by modification All organisms are related by ties of genealogy or descent from common ancestry 2013 W. Brian Arthur 2

4 Darwin s Mechanism It is the steady accumulation through natural selection of such differences, that gives rise to all the important modifications of structure. Complex organ[s] formed by numerous, successive, slight modifications Problem: This doesn t work for technology 2013 W. Brian Arthur 3

5 If technology evolves, what is the mechanism? We are looking for a mechanism of heredity in the origin of novel technologies in invention 2013 W. Brian Arthur 4

6 Invention is a process Linking a need with the idea of some effect that will fulfill it This poses sub-problems. They too need the idea of some effect Recursive iteration follows Problem resolved when all these have been resolved satisfactorily Result: A combination 2013 W. Brian Arthur 5

7 Example: Gary Starkweather 1972 Problem: How to print images from a computer Several possible principles 2013 W. Brian Arthur 6

8 Gary Starkweather s problem 1972 Possible principle: Use a laser to paint images on a Xerox drum Sub-problems: Modulating the laser Moving the laser rapidly Use a mirror Problem of lining up the mirror facets» Solve this optically 2013 W. Brian Arthur 7

9 Laser printer 2013 W. Brian Arthur 8

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11 RADAR W. Brian Arthur

12 Combinatorial Evolution Technologies form a vast chemistry of elements, that in combination give rise to (make possible) further elements 11

13 The collective of technology is a vast ancestral network that creates new nodes from existing (parental) ones It is autopoietic: new elements build from existing ones Complication builds from simplicity 12

14 The economy builds out as its technologies build out In the beginning, the first phenomena to be harnessed were available directly in nature. Certain materials flake when chipped: whence bladed tools. Heavy objects crush materials when pounded against hard surfaces: whence the grinding of herbs and seeds. These phenomena, lying on the floor of nature as it were, made possible primitive tools and techniques. These in turn made possible yet others. Fire made possible cooking, the hollowing out of logs for primitive canoes, the firing of pottery. Combinations of elements began to occur: thongs or cords of braided fibers were used to haft metal to wood for axes. Clusters of technology and crafts of practice dying, potting, weaving, mining, metal smithing, boat building began to emerge. Wind and water energy were harnessed for power. Combinations of levers, pulleys, cranks, ropes, and toothed gears appeared early machines and were used for milling grains, irrigation, construction, and timekeeping. In time, the chemical, optical, thermodynamic, and electrical phenomena began to be understood and captured. The large domains of technology came on line: heat engines, industrial chemistry, electricity, electronics. and with these still finer phenomena were captured: X-radiation, radio-wave transmission, coherent light. And with laser optics, radio transmission, and logic circuit elements in a vast array of different combinations, modern telecommunications and computation were born. In this way, the few became many, and the many became specialized, and the specialized uncovered still further phenomena and made possible the finer and finer use of nature s principles W. Brian Arthur 14

15 This suggests an evolutionary algorithm Start with a soup of elements Form combinations (possibly at random) from this If a combination is useful, encapsulate and preserve it Add new combination to soup as a building block element 2013 W. Brian Arthur 13

16 Cf. Darwin s evolutionary algorithm Start with a population that produces variations Select differentially New population produces further variations Population diverges by steady accumulation of small changes 2013 W. Brian Arthur 13

17 Combinatorial Evolution in the Lab. An expt. W. Brian Arthur and Wolfgang Polak (2006) Idea Create an artificial world in which technologies evolve indefinitely from previous ones. I.e. Allow the system to create technologies by combining previous technologies The technologies will be logic circuits 14

18 How the experiment works 1. Start from one primitive element (a NAND gate) and a wishlist of needs (target logic purposes) 2. Make circuits by random combination of existing elements 3. Check to see if any needs are fulfilled 4. If so, these novel circuits become encapsulated and used as new building blocks 15

19 After 250,000 steps Quite complicated circuits have evolved 8-way EXOR, 8-way AND, 4-bit EQUALS, 8-bit COMPARATOR, etc. An 8-bit ADDER (16 inputs, 9 outputs). This is one of ,554 possible circuits 16

20 The experiment 1. Shows path-dependence Shows a Cambrian explosion Shows that intermediate circuits need to appear before it can produce complicated ones 17

21 Combinatorial Evolution occurs in: Various chemistries Genetic regulatory networks Physical cosmos Mathematics The collective of technology 18

22 Biological vs. Technological Evolution Biological: Darwinian variation and selection, accumulation of incremental changes Combination occurs too Technological: Combinatorial, abrupt, encapsulates self-augmenting Much Darwinian evolution once a technology exists 19

23 Summary There exists a second mechanism of evolution, Combinatorial Evolution. It occurs in many systems Technology indeed evolves, primarily through this mechanism of Combinatorial Evolution (rather than Darwin s mechanism) 2013 W. Brian Arthur 21

24 François Jacob In our universe, matter is arranged in a hierarchy of structures by successive integrations. Whether inanimate or living, the objects found on earth are always organizations or systems. Each system at a given level uses as its ingredients some systems from the simpler level. The great diversity of vertebrates results from differences in the arrangement, in the number and distribution, of these few [building blocks]. 20

25 William Fielding Ogburn Social Change, 1922 Ogburn s Claim (1922) inventions. When the existing material culture is small, embracing a stone technique and a knowledge of skins and some woodwork, the number of inventions is more limited than when the culture consists of a knowledge of a variety of m etals and chemicals and the use of steam, electricity, and various mechanical principles such as the screw, the wheel, the lever, the piston, belts, pulleys, etc. The street car could not h ave been invented from the material culture existing at the last glacial period. The discovery of the power of steam and the mechanical technology existing at the time made possible a l arge number of It would seem that the larger the equipment of material culture, the greater the number of inventions. The more there is to invent with, the greater will be th e number of 2012 W. Brian inventions. Arthur 25 15

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