Some ideas, objects and events are so far away or so great that it is difficult to imagine them. The space, history, inventions, life on earth ... what would happen to them? The author of "If ...", David Smith, uses scale reduction to make the great ideas understandable and the great numbers that surround us and show us the world in a completely new and surprising way. If the sun had the size of a grapefruit, the earth would be a grain of salt and Jupiter would not be bigger than a pebble. If all the water of the earth was represented by 100 glasses, only 3 would contain all the fresh water of our planet. If the 3.5 billion years of life on earth were condensed in one hour, the dinosaurs would not appear before 56 minutes and would disappear 3 minutes later. Reading age: for 7 years.