This book is already a decade old and yet, it has become a classic. The Swiss author and entrepreneur, Rolf Dobelli, aims at giving insight into human reasoning and decision-making. He does it in a very succinct way: the compilation of 99 chapters of a few pages each barely scratches the surface of cognitive biases. We all have them. One way or the other, we decide to keep doing something we know is not good for us. Or to disregard information that would have us change our way of thinking and seeing things that we have been used to. These are just common examples and this book invites each one of us to do some introspection on the biases we, sometimes unconsciously, resort to. It is true that Dobelli has not invented anything new here and that the easy and short read isn't rocket science. It remains a good reminder that thinking is an art. And the better we master it, the greater things we can achieve, and the happier we would be. When armed with a clear mind, we would not overestimate our abilities, we would understand that we do not control anything in life, we would not necessarily follow the social masses, we would broaden our attention while focusing on making informed decisions, and try to think as rationally as possible. So even "if 50 million people say something foolish, it is still foolish"... Happy reading 📚