Science rules the world. Clothing, food, houses, television - everything that humanity can create today is based on scientific knowledge. Scientific discoveries in medicine and biology help preserve health. Thanks to modern science, we know so much about the world around us. However, this was not always the case. Only a couple of thousand years have passed since people began to know the world around them scientifically. Scientific progress has always been about putting forward a hypothesis, an assumption that might seem crazy at first. It is these assumptions that later became the fundamental concepts of modern science that are discussed in this book.