The Measure of Reality:
Quantification and Western Society, 1250-1600

Always a pleasure to read, Alfred Crosby this time searches for answers to the question, "Why did Europeans begin exploring the larger world when they did, and not before?" in his book The Measure of Reality: Quantification and Western Society, 1250-1600. He argues that it was due to an epochal shift from the ancient qualitative to the new quantitative model of perception in Western Europe beginning in the late Middle Ages and continuing through the Renaissance.

Myriad changes occurred during this time that made possible modern science, technology (such as mechanical clocks), business practice (such as double-entry bookkeeping), and bureaucracy. Another example of change is that seen in maps. Geometrically precise maps meant navigators could accurately pin-point their position on a given coastline, follow the route of another's travels, and expand their knowledge of previously unknown territory.

Many cycles of advancement and retreat were made as information was gained and horrors such as the Black Death stymied its dispersal. Despite the gain-loss-gain-loss cycle of new knowledge, quantification grew to a passion among Europeans and became a norm in their lives, and, eventually, in ours.

What fueled this rising passion for quantification? Hindu-Arabic numerals were very important; they were much easier to use than the then-common Roman numerals. The shift to the visual was also important and is found in perspective painting and literacy (rather than the simple oral transmission of information). Mathematics moved away from simple equations tallied on fingers to algebraic expressions. Music was no longer reproduced by one singer listening to another and memorizing the words, notes, and tune but by notations written on paper.

Taken individually, the stories of any of these advances in conveying information make an interesting historical tale. Together they show us the all-encompassing change that revolutionized human thought in Western Europe and made it possible for the adventuresome to explore an emerging global world in drastic new ways.