Not only are humans 1) unique in the sense that they began to use an ever-widening tool set, we are also the only species on this planet that has constructed forms of complexity that use external energy sources. This was a fundamental new development, 2) which there were no precedents in big history. This capacity may first have emerged between 1.5 and 0.5 million years ago, when humans began to control fire. From at least 50,000 years ago, some of the energy stored in air and water flows 3) was used for navigation and, much later, also for powering the first machines. Around 10,000 years ago, humans learned to cultivate plants and 4) tame animals and thus control these important matter and energy flows. Very soon, they also learned to use animal muscle power. About 250 years ago, fossil fuels began to be used on a large scale for powering machines of many different kinds, thereby 5) creating the virtually unlimited amounts of artificial complexity that we are familiar with today.