The Printing Press

Gutenberg's 1440 printing press is the most impactful device for democratizing knowledge before the Internet (#1). By reducing the cost of book production by over 80% compared to hand-copying, it spread scientific ideas 400 times faster across Europe, fueling the Renaissance and Reformation. Cheaper than the typical manuscript of the era by a factor of 300, it shifted literacy from 10% to over 60% in major cities within a century, laying the groundwork for modern science. This created a knowledge explosion that outperforms electricity (#4) in cultural reach, with over 20 million books printed across Europe by the 16th century.