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Figure 6. The autocatakinetic flow of the fluid constituting a Bénard cell is shown by the small arrows. T(1) to T(2) is the heat gradient between the heat source below and the sink above that constitutes the potential that motivates the flow. Because density varies inversely with temperature there is also a density gradient from bottom to top giving groups of molecules ("parcels") that are displaced upwards by stochastic collisions an upward buoyant force. If the potential is above the minimum threshold parcels will move upward at a faster rate than their excess heat can be dissipated to their surrounds. At the same time such an upward flow of heat will increase the temperature of the upper surface directly above it creating a surface tension gradient which will act to further amplify the upward flow by pulling the hotter fluid to the cooler surrounds. The upward displacement of fluid creates a vacuum effect pulling more heated fluid from the bottom in behind it which in turns makes room for the fluid which has been cooled by its movement across the top to fall, be heated and carry the cycle on, and autocatakinesis has been established. From R. Swenson, 1997, Hillsdale, NJ: Lawrence Erlbaum and Associates. Copyright 1997 by Lawrence Erlbaum and Associates. Used by Permission.
space-time dimensions and order production we can get a physical understanding of how this works.
     Figure 6 is a schematic drawing of the generalized pattern of flow that defines the new space-time level in the ordered regime of the Bénard experiment. It shows the ordered flow moving hot fluid up from the bottom through the center, across the top surface where it is cooled by the air, and down the sides where it pulls in more potential as it moves across the bottom and then rises through the center again as the cycle repeats. Figure 7 shows the dramatic increase in entropy production that occurs with the switch to the ordered regime, and this is just what we would expect from the balance equation of the second law. Ordered flow must function to increase the rate of entropy production of the system plus environment, must pull in sufficient resources and dissipate them, to satisfy the balance equation. Ordered flow, in other words, must be more efficient at dissipating potentials than disordered flow, and in Figure 6 we see how this works in a simple physical system. The fact that ordered flow is more

 
Figure 7. The discontinuous increase in the rate of heat transport that follows from the disorder-to-order transition in a simple fluid experiment similar to that shown in Figure 5. The rate of heat transport in the disordered regime is given by k , and k +s is the heat transport in the ordered regime [3.1 x 10-4H(cal x cm.-2 x sec-1)]. From R. Swenson, in M. Rogers and N. Warren (Eds.), A Delicate Balance: Technics, Culture and Consequences (p. 70), 1989a, Los Angeles: Institute of Electrical and Electronic Engineers (IEEE). Copyright 1989 IEEE. Reprinted by permission.


efficient at minimizing potentials brings us to the final piece in the puzzle.

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