The question is not whether we like the conclusion that emerges out of a train of reasoning, but whether the conclusion follows from the premise, or starting point, and whether that premise is true. 

Among the tools: 

• Wherever possible there must be independent confirmation of the facts
• Encourage substantive debate on the evidence by knowledgeable proponents of all points of view
• Arguments from authority carry little weight 
• Spin more than one hypothesis
• Try not to get overly attached to a hypothesis just because its yours
• Quantify if whatever it is you’re explaining has some measure, some numerical quantity attached to it, you’ll be much better able to discriminate among competing hypotheses
• If there’s a chain of argument, every link in the chain must work, including the premise, not just most of them
• Occam’s razor 
• Always ask whether the hypothesis can be, at least in principle, falsified

This book is seminal in my mind. It was timeless in its approach to detractors of scientific reasoning. Just the section above from Sagan was worth the price of the book. 

The topics Sagan went into were centered around conspiracy theories of the time -UFOs, Extraterrestrial Life Forms, and Religious explanations of the natural world. Not much has changed, but the examples used hold a lot of value for addressing the detractors of science and logic applied to complex thoughts such as where did something come from or why does something exist. 

The best part, in my opinion, was the rationale: at some point we did not fully understand something and formed a hypothesis based on available knowledge of the time. For instance, do we revolve around the sun or vice versa? We know better now, but at one point we did not know the answer. It took quite a while to form a conclusion as to why the earth orbits the sun. 

Even with overwhelming evidence, there are detractors who convolute evidence. For instance, flat earth believers. This idea may sound crazy, but to some it is completely rational to question that the earth is round. It is the classic short sided rationale of seeing what is directly in front of us. I cannot see the horizon bend, so therefore it must be straight. 

How much of this are we dealing with in health and fitness? We are constantly being scrutinized for being a ‘work in progress’ science. Having outsiders give their distilled down, absolute reasoning to something makes people confused and they begin to question everything. Sagan’s approach to handling non-believers is something we as coaches should consider (if you like this book you should read Dr Richard Feynman’s work as well). 

Taking a scientific approach to training means taking an approach that is devoid of bias and agenda. Handling people with pseudo logic to what someone might need should be met with a healthy skepticism and an open mind. Sagan did an excellent job of laying out the pitfalls of negatively associating bias with people and being elitist towards people. That is the fastest way to make someone disagree with you! 

Great book, highly recommended.