Against the Gods: The Remarkable Story of Risk Read Online Free Page B

closer
to quantifying risk. But here, too, we find no indication that they followed up on their reasoning by developing a methodical approach to
risk. Sambursky cites a passage in the Talmud, Kethuboth 9q, where the
philosopher explains that a man may divorce his wife for adultery without any penalty, but not if he claims that the adultery occurred before
marriage. 13
age.
    "It is a double doubt," declares the Talmud. If it is established
(method unspecified) that the bride came to the marriage bed no longer
a virgin, one side of the double doubt is whether the man responsible
was the prospective groom himself-whether the event occurred
"under him ... or not under him." As to the second side of the doubt,
the argument continues: "And if you say that it was under him, there is doubt whether it was by violence or by her free will." Each side of
the double doubt is given a 50-50 chance. With impressive statistical
sophistication, the philosophers conclude that there is only one chance
in four (1/2 x 1/2) that the woman committed adultery before marriage. Therefore, the husband cannot divorce her on those grounds.

    One is tempted to assume that the lapse of time between the invention of the astragalus and the invention of the laws of probability was
nothing more than a historical accident. The Greeks and the Talmudic
scholars were so maddeningly close to the analysis that Pascal and
Fermat would undertake centuries later that only a slight push would
have moved them on to the next step.
    That the push did not occur was not an accident. Before a society
could incorporate the concept of risk into its culture, change would have
to come, not in views of the present, but in attitudes about the future.
    Up to the time of the Renaissance, people perceived the future as
little more than a matter of luck or the result of random variations, and
most of their decisions were driven by instinct. When the conditions of
life are so closely linked to nature, not much is left to human control.
As long as the demands of survival limit people to the basic functions of
bearing children, growing crops, hunting, fishing, and providing shelter, they are simply unable to conceive of circumstances in which they
might be able to influence the outcomes of their decisions. A penny
saved is not a penny earned unless the future is something more than a
black hole.
    Over the centuries, at least until the Crusades, most people met
with few surprises as they ambled along from day to day. Nestled in a
stable social structure, they gave little heed to the wars that swept across
the land, to the occasions when bad rulers succeeded good ones, and
even to the permutations of religions. Weather was the most apparent
variable. As the Egyptologist Henri Frankfort has remarked, "The past
and the future-far from being a matter of concern-were wholly
implicit in the present."14
    Despite the persistence of this attitude toward the future, civilization made great strides over the centuries. Clearly the absence of modern views about risk was no obstacle. At the same time, the advance of civilization was not in itself a sufficient condition to motivate curious people to explore the possibilities of scientific forecasting.

    As Christianity spread across the western world, the will of a single God emerged as the orienting guide to the future, replacing the miscellany of deities people had worshiped since the beginning of time. This brought a major shift in perception: the future of life on earth remained a mystery, but it was now prescribed by a power whose intentions and standards were clear to all who took the time to learn them.
    As contemplation of the future became a matter of moral behavior and faith, the future no longer appeared quite as inscrutable as it had. Nevertheless, it was still not susceptible to any sort of mathematical expectation. The early Christians limited their prophecies to what would happen in the afterlife, no matter