How inventions change history (for better and for worse) - Kenneth C. Davis

View full lesson: Invented in 1793, the cotton gin changed history for good and bad. By allowing one field hand to do the work of 10, it powered a new industry that brought wealth and power to the American South -- but, tragically, it also multiplied and prolonged the use of slave labor. Kenneth C. Davis lauds innovation, while warning us of unintended consequences. Lesson by Kenneth C. Davis, animation by Sunni Brown.