The lesson of the pencil
Milton Friedman talks about the pencil, a free economy, and peace in the world here.
Brits invented pencils in the 16th century, invented erasers "rubber" in the 18th century, figured out how to prevent rubber from being sticky in summer and brittle in winter, and brought the rubber tree that provides erasers to Malaysia from Brazil in the 19th century. For details see Ingenious Timeline.
The free economy that Adam Smith first described and that Brits first established brings people from South America, Malaysia, and America together in peace to earn a living and to put that pencil in our hands for a "trifling sum".