What can we know? This question, as old as philosophy itself, has recently acquired new meanings and received new answers from a vast array of sciences, ranging from computer science to biology and from mathematics to economics. Pascal Brandys, a generalist experienced by decades of interaction with scientists, takes us on a journey of discovery of these recent developments. The dialogue between two characters, one semi-omniscient and the other simply curious, always remains accessible but quickly leads us from the cutting edge of current theories to far-reaching conclusions and novel ideas. In this realist analysis, unknowability appears much closer to us than we think. We have already achieved an impressive level of knowledge of many complex matters, including life, but other seemingly obvious things, such as numbers, are sure to escape us completely. At the end, it seems that the very tools we create to increase our investigational powers are simultaneously unveiling new classes of unknowable truths. But the conclusion is optimistic; there is still a lot to know, starting with this book!

To know or not to know? That is indeed the question for contemporary science. This book takes us to the cutting edge of theories and ideas surrounding unknowability.