>The number of building blocks is so large that it is not feasible to calculate explicitly the estimates of schema fitness that would guide increased or decreased usage of given building blocks.
>The genetic algorhythm does implicitly what is not feasible explicitly.  The whole-string operations (reproduction, crossover and mutation) directly deal with schemata and carry out no computations involving them.  Yet the algorhythm acts as if such computations were actually being made and exploited.
>Above average schemata of one generation are used more frequently in the next generation, and below average schemata are used less frequently.  This ability to manipulate large numbers of schemata implicitly through explicit manipulation of a relatively small number of strings is called implicit parallelism.
   
In computer science, implicit parallelism is a characteristic of a programming language that allows a compiler or interpreter to automatically exploit the parallelism inherent to the computations expressed by some of the language's constructs. A pure implicitly parallel language does not need special directives, operators or functions to enable parallel execution.

In computer science, concurrency is a property of systems in which several computations are executing and overlapping in time, and potentially interacting with each other. The overlapping computations may be executing on multiple cores in the same chip, preemptively time-shared threads on the same processor, or executed on physically separated processors

>Viewing rule discovery in terms of building block manipulation and implicit parallelism changes the outlook in another way.  Consider a biological population, say a human population.  No individual in a given generation is identical to any individual in the previous generation.  There will only, ever, be one Einstein.  Here we have a bit of a dilemma.  If evolution “forgets” the best individuals in each generation, what does it “remember’?
>Implicit parallelism provides an answer.  Particular individuals do not recur, but their building blocks do.
>This recurrence of building blocks is a familiar feature of artificial breeding.  Every thoroughbred breeder knows that certain features are associated with certain bloodlines.  These are the building blocks that are combined by selective crossbreeding.  Though we will never again see a Man O' War, or a Citation, their building blocks appear again and again.