Is flying dangerous? How much do the world's cows weigh? And what makes people happy? From earth's nations and inhabitants, through the fuels and foods that energize them, to the transportation and inventions of our modern world - and how all of this affects the planet itself - in Numbers Don't Lie, Professor Vaclav Smil takes us on a fact-finding adventure, using surprising statistics and illuminating graphs to challenge lazy thinking. Packed with 'well-I-never-knew-that' information and with fascinating and unusual examples throughout, we see how it is too soon to judge shale gas, that vaccination yields the best return on investment, and why electric cars aren't as great as we think (yet). There's a wonderful mix of science, history and wit, all in bite-sized chapters on a broad range of topics. Should you trust unemployment figures? Is China's rise unstoppable? And what's worse for the environment: your car or mobile phone? Unclouded by pessimism or optimism and unafraid of big questions, Smil explains why calls for the Anthropocene era may be premature but why the Paris Agreement does not go far enough. These issues are not straightforward and progress takes longer than you think, but with Smil as our authoritative and entertaining guide we get a healthy shot of realism. Urgent and essential, Numbers Don't Lie is a powerful rallying cry for interrogating what you take to be true in these significant times. Smil is on a mission to make facts matter, because after all, numbers may not lie, but which truth do they convey?