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70 Demonstrating the complexity of a process is different from demonstrating that the end result is rare. am All physical processes are a combination of chance and necessity, Nobel Prize winner Jacques Monod wrote in 1971. If chance was the dominant factor, the probability of a known organism forming from random molecu- lar shuffling is absurdly small. Others have challenged this view, arguing that Monod had elevated chance to the level of a metaphysical principle; any scientific explanation that uses the hypothesis of singular chance comes into conflict with scientific standards." Nonetheless, evolution could have gone in different directions at many stages, producing very different results. The evolutionary process is not directional, orthodox Darwinists declare, and does not produce predict- abla aete able outcomes. Biologist Leonard Ornstein spoke for many when he argued that Darwinian selection is unparalleled by other physical processes and is much less likely to repeat itself. Evolution on Earth can easily have gener- ated many “inventions,” perhaps including intelligence, which are unique in the universe. He then went beyond science to declare that no significant social expenditure on SETI is warranted.” Nobel Prize winning biologist Francois Jacob proposed that the appear- ance of life on our planet was not the necessary consequence of the pres- ence of certain molecular structures in prebiotic times. “In fact,” he wrote, “there is absolutely no way of estimating what was the probability for life appearing on Earth.” The living world as we know it is just one among many possibilities; its actual structure results from the history of our planet. The interplay of local opportunities—physical, ecological, and constitutional— produces a net historical opportunity that determines how genetic oppor- tunities will be exploited. It is this net opportunity that controls the direction and pace of adaptive evolution. As for extraterrestrial life, the sequence of historical opportunities there could not be the same as here." ane Oatateecd tented a4 akin 4 ten Aree. Astronomer George Seielstad looked at this question in a different way. Could life have been a certainty sometime, simply because its ingre- dients were periodically reshuffled until appropriate conditions fell into place?* Scientists have found that the course of evolution is characterized by a trend to greater flexibility in the execution of the genetic program. With each innovation improving the transmission of genetic information, argued zoologist Mark Ridley, the complexity ceiling rose. Genomes may have potential capabilities that are hidden in normal times; organisms may be able to draw on preexisting genetic variation in response to environmental Probabilities: Life Chancists Versus Convergionists —Physicist Lawrence Krauss, 2000"