When We Cease to Understand the World shows us great minds striking out into dangerous, uncharted terrain. Fritz Haber, Alexander Grothendieck, Werner Heisenberg, Erwin Schroedinger: these are among the luminaries into whose troubled minds we are thrust as they grapple with the most profound questions of existence. They have strokes of unparalleled genius, they alienate friends and lovers, they descend into isolated states of madness. Some of their discoveries revolutionise our world for the better; others pave the way to chaos and unimaginable suffering. The lines are never clear. At breakneck pace and with wondrous detail, Benjamin Labatut uses the imaginative resources of fiction to break open the stories of scientists and mathematicians who expanded our notions of the possible.