Auto-Didact said:
Halfway through now. The book so far is both an informal history of mathematics and its key discovers. Around the middle is where he arrives at Newton and Leibniz. Along the way I have learned a few things e.g. that Fermat actually invented the Cartesian plane before Descartes did and he even almost invented the derivative as well.
Strogatz does a very good job of balancing contributions for every major historical step, the two key figures which were involved in the invention and how the stark contrast in their thinking based on completely different viewpoints of the subject leads to two very different approaches to some mathematical idea. The miracle of mathematics is that these dual approaches - logically often the complete opposite - are capable of converging to a single idea.
These two different approaches are key to understanding both the practice of mathematics and the subject of calculus, i.e. both actually discovering new mathematics and refining what is discovered as well as understanding what infinity can do for us. Strogatz manages to illustrate the very different nature of symbolic mathematics as mathematics progressed through the centuries, giving an introduction to the concept and primacy of mathematical creativity based on synthesis in contrast to proof by formal analysis.
Synthesis is an informal method/subject invented by the ancient geometers and used since by many mathematicians (and physicists) based on physical intuition. Synthesis as a method tends to be entirely overlooked or ignored in modern math education; this is starkly clear in that calculus is seen as part of analysis with no mention of synthesis whatsoever.
Together with analysis, synthesis enables the possibility of finding answers and proving that the found answers are correct. The problem is that synthesis has been almost universally rejected in public by mathematicians and in mathematics education after Hilbert. It helps very much that Strogatz is one of the greatest applied mathematicians alive and willing to speak so casually about this, both in public, in his textbooks and in his popular books.
@A. Neumaier and
@fresh_42, I recall having discussions on this with you on this topic before: the distinct usage of synthesis and symbolic mathematics is why Newton can truly be considered to be the first mathematical physicist, and not Kepler or Galileo despite their physics being presented in mathematical form.
Being in mathematical form is a necessary but not sufficient condition for something to be deemed part of 'mathematical physics' (or analogously 'mathematical biology' or 'mathematical economics', etc); if this were sufficient then any physics argument based on statistical argument would be considered to be 'mathematical physics'.
Kepler's laws were based on non-synthetic reasoning but instead result from statistical analysis of measurements. This is in stark contrast to Newton who derived Kepler's laws from first principles based on his concept of force. It is the qualitative leap in thinking i.e. the usage of synthetic methodology which makes Newton's work to be a new subject called mathematical physics.