The lectures which make up this volume are all intriguing and well-written, but I only occasionally found them deeply engaging. Perhaps that's because I am already pretty familiar with the broader philosophical perspective--particularly in its Heideggerian strands--which informs Mumford's observations about technology and art, and thus found him somewhat repetitive; it also might be that I'm just too informed by the specialized study of history from the past two generations to be entirely content with his broad, sweeping historical accounts, even allowing for the fact that these were lectures, not scholarly monographs. Anyway, the final lecture, "Art, Technics, and Cultural Integration," was especially good; I never thought of Mumford as a Hegelian, but to my reading his quotations from Spengler and others absolutely put him in that camp. Overall, some challenging and important ideas, even if they weren't, to me, the best possible expression of them.