Oil is one of the oldest fuel sources known to man. Its impact on the world is not simple; while it has powered the vehicles that have made human mobility possible, it has also propped up some of the most repressive regimes in recent history. In the last installment of our four-part history of energy series, we speak to journalist and author Paul Roberts to discuss the complex role that oil has played in shaping the industrialized world, and the costs/benefits that oil has as an energy source in the 21st century.

Paul Roberts is a journalist and author who covers energy and technology. His work has appeared in many publications including Rolling Stone, Harpers, and the Washington Post. His book The End of Oil (2004), examines the history of petroleum and its impact on the world.

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