The late 18th Century was the beginning of the Enlightenment and the Age of Reason, a turning point in history when science was breaking new ground into the mysteries of nature. It makes sense to set the story during this period, when we were just beginning to find out about such things as our control over nature, rather than at a later date when scientific truths were better established. The Enlightenment was also a period of secular philosophy (such as the works of Locke, Hume, Voltaire, Rousseau, etc), but this poses such questions as: do we have the right to play God? Are we really masters of our own destiny? What happens if we tamper too much with nature? (By the way, don't be put off by humorous answers. Some of us regulars like to lighten the conversation sometimes.). Hope I've helped.