Taking into account the current experimental and technological accomplishments and theoretical methods, this book stresses the basic laws of science, i.e. Archimedes principle, Newton's laws, and critically analyses these laws. Generalization of the laws and principle are inevitable. Newton did not discover the Second Law of Motion, F = ma. This is is clear from the critical study of the Principia. In the existing literature there is no quantitative theory which may explain the phenomena of rising, falling and floating bodies quantitatively. Such a theory is described in the book for first time.