The technologies which have had the most profound effects on human life are usually simple. A good example of a simple technology with profound historical consequences is hay. ... It was hay that allowed populations to grow and civilizations to flourish among the forests of Northern Europe. Hay moved the greatness of Rome to Paris and London, and later to Berlin and Moscow and New York.
[The year-round growth of green grass in the Mediterranean climate meant that hay was not needed by the Romans. North of the Alps, hay maintained horses and oxen and thus their motive power, and productivity.]

[When I was a child] I grew up in Brooklyn, New York, and I was a street kid. ... [T]here was one aspect of that environment that, for some reason, struck me as different, and that was the stars. ... I could tell they were lights in the sky, but that wasn't an explanation. I mean, what were they? Little electric bulbs on long black wires, so you couldn't see what they were held up by? What were they? ... My mother said to me, "Look, we've just got you a library card ... get out a book and find the answer." ... It was in there. It was stunning. The answer was that the Sun was a star, except very far away. ... The dazzling idea of a universe vast beyond imagining swept over me. ... I sensed awe.