Abstract

During antiquity, the astronomical questions of the day and the methods used to formulate and answer them were clearly within the realm of philosophy. That changed most notably in the sixteenth century when Tycho Brahe turned astronomy into a modern empirical science by formulating (in principle) testable hypotheses, figuring out how to test them, building the proper instruments, and making – for that time – very accurate and systematic observations of the sky. These observations eventually led to the modern view of the solar system and ultimately the rejection of the classical Aristotelian worldview. Since then, the exploration of space has been located clearly in the realm of natural science – and, to an increasing extent, technology. In parallel to that, space has – at least since World War II –to a high degree been a place for military and political ambitions and activities. The scientists that have been involved in space exploration have mainly been physicists, together with some chemists and geologists. Lately, the exploration of space has engaged more and more biologists in the search for extraterrestrial life. The international space station, along with plans to send humans to Mars, has led to an increased involvement of medical science. If present speculations about space tourism and mining on planets, moons, and asteroids hold true, in the future we will probably see many new professions dealing not just with exploration, but also exploitation of space. Philosophy has never totally left the realm of space exploration. As space exploration and exploitation become more and more interdisciplinary, and as space becomes a bigger part of our lives, it will be time once more for philosophy to turn its attention towards space. The mission for philosophers is not to indulge in speculations over questions that are better dealt with by empirical methods. Ther are, however, several questions connected to the exploration and exploitation of space that are of a philosophical nature and that deserve to be examined seriously from a philosophical perspective. I believe that philosophical scrutiny of these questions will be to the benefit of both space exploration and philosophy. Interesting and, indeed, important philosophical questions arise in many areas of space exploration. Some of the most interesting and important ones relate to the search for extraterrestrial life, of which some will be presented here. I will not attempt to answer these questions here. Instead, this chapter should be seen as an introduction to some of the philosophical questions raised by astrobiology.