The Uses of Diversity. David Ellerman
as two opposing moments in one overall process. Think of a species as trying to climb to a higher level of evolutionary fitness on a “fitness landscape” that has multiple peaks. But the species might be on a low hill. From Darwin up until Sewall Wright’s work in the early 1930s, evolutionary theory focused on selection which by itself is only a hill-climbing mechanism. If the main population is climbing a low “dead-end” hill, then there needs to be some alternative way to go downhill against selective pressures, cross a valley of low fitness, and start climbing a higher hill. Mutation in one large interbreeding population was not enough. Sewall Wright was the first evolutionary thinker to focus on that problem of variation, exploration, and diversification. “The problem of evolution as I see it is that of a mechanism by which the species may continually find its way from lower to higher peaks in such a field” (Wright 1932; reprinted in Wright 1986, 163–64).
The solution10 was again diverse semi-isolated experiments (subpopulations or “demes” in different niches) run in parallel with enough migration of genes between the subpopulations so that successes would ratchet up the whole population. Since there was always a balance to be struck between the semi-isolation of the subpopulations to encourage novelty, and communication between the groups to share successes, Wright called it the “shifting balance theory.”
As a general scheme of parallel experimentation for learning under uncertainty (where you really don’t know the One Best Way to go), the “Wright stuff” are different experiments running concurrently
• with some common goal (rather than focusing resources on what currently seems like the best option),
• with some semi-isolation from the pressure of immediate success,
• with benchmarking comparisons made between the experiments, and
• with the “migration” of discoveries between experiments wherever possible to ratchet up the performance of the whole population.11
The Jacobs’ Ladder mechanism is, of course, an example of a parallel experimentation scheme. The different cities (or countries) within a vibrant trading bloc are each carrying on various experiments and then exporting their successes to others in the group. Each member tries to incorporate and improve upon the “challenging” imports and then to reexport their successes so that they develop “on each other’s shoulders” ratcheting up the level of development (knowledge and productive capacity) of the whole group.
Such a scheme of mutual challenges and import replacements ratcheting up and continuously improving the whole trading bloc is in striking contrast to the scheme promoted by comparative advantage theory in which each city, region, or country in the trading bloc specializes in “what it does (relatively) best” and then exports that product (perhaps ever-improving through more specialization) to the other specialized trading partners who, in turn, supply their ever-improving specialized products as imports to the others in the bloc. Jacobs sees this scheme of specialization as a recipe for long-term stagnation. People with specialties can further dynamic improvements if they jostle together with people of other specialties within a company. Or companies with specialties can promote dynamics if they jostle together with other companies within a versatile city. But when a whole city specializes and trades with other specialized cities, then that locked-in pattern of static efficiency is a recipe for stasis and long-term decline.
Jacobs University: A School for Lifetime Learning
It is not easy to explain Jacobs’s theory in terms of conventional economic models. Perhaps one key is to focus on her theory of development as a type of social learning and then to construct a purely educational analogue as an aid to understanding. That is the purpose of this section.
Imagine a school of people who are both students and teachers. They earn chits by teaching some topic to their fellow students, and then they can use the chits to pay for courses offered on other topics by their fellow student-teachers. For simplicity, we assume that the student-teachers’ other needs are taken care of by other means, for example they are like students living at home. As students learn and can recombine knowledge and innovate, they may offer new courses to their fellows if they can find enough takers. The student-teachers play the role of the cities with the courses they teach being their “exports” and the courses taken being their “imports.” Thus, Jacobs University is a simplified educational model of the Jacobs’ Ladder mechanism. The student-teachers learn (develop) on each other’s shoulders. Many of her basic arguments can be modeled and perhaps clarified within the Jacobs University model. The arguments are developed in parallel in table 1.1.
Table 1.1 An Educational Analogy for Jacobs’s Economic Theory
| Theme | Economic Model:Jacobs’ Ladder Mechanism | Educational Model: Jacobs University for Lifetime Learning |
| Players | Cities. | Student-teachers. |
| Inputs | Imports. | Courses taken by students. |
| Outputs | Exports. | Teaching fellow students. |
| Means of obtaining inputs | Exports earning imports. | Teaching other students to earn chits to pay other student-teachers to teach one a new topic. |
| Original endowment | Endowment of natural resources to start process (as original unearned resources to buy imports). | Inherited chits to start taking a course. |
| How success forces players to next level | Exports to a creative city will soon be replaced forcing a city to generate new exports. | Courses successfully taught will dry up the students willing to take the same course, so teacher has to learn something new to teach. |
| Desert | Imports (however funded) are just consumed with no attempt to stretch or replace them. | Course taken (however funded) but no learning and no subsequent teaching. |
| Rain forest | Imports are assimilated, stretched, and modified in a diversity of products. City is in an excellent position to innovate and export goods. This is easier in a diverse city with many entry points to assimilate and creatively use imports. | Course knowledge feeds into a number of “hooks” or “entry points” so a student has an in-depth understanding of topic and is in an excellent position to teach—perhaps in new courses. This is easier in a student with more diverse knowledge. |
| Export processing zone | Imports get a little processing and are then reexported. | Courses not really learned but mechanically used to teach others with little real understanding oneself. |
| Advanced-backward trade | Science fiction import cannot be stretched or replaced. Not assimilated in that sense. Stops the dynamic. | Course at too advanced level so little is learned or assimilated. Stops the dynamic. |
| Supply regions | Regions that produce something, natural resources, agricultural outputs, or a military supplier that is not part of a Jacobs’ Ladder dynamic (inert partners with steady demand) so it is lulled into just using its earnings to buy imports and has lost the necessity and capacity to replace the imports. It has stopped learning and becomes specialized. |
Finds that teaching in a specific field goes on and on so one can take other courses but it is not really necessary to learn them to teach in the new topics. Slides outside the dynamic of teaching, students learning to teach, teacher needing to learn a new topic, |