In a world of uncertainty, it can be tempting to wish for definitive answers: the one right way to practice yoga, the one right diet to follow, the one right way to live. However, particularly in a time when anyone can publish anything, it is easy to find contradictory answers to any question. Read on to explore the topic of critical thinking in an exclusive excerpt from The Physiology of Yoga. You’ll find tips on how to navigate all the conflicting views and opinions that are shared about many topics in the yoga world.
We probably like to believe that we think logically, reasonably, and without bias, but that is not always so. According to philosopher-educators Paul Richard and Linda Elder, two important figures in the development of critical thinking, “Much of our thinking, left to itself, is biased, distorted, partial, uninformed or down-right prejudiced. Yet the quality of our life and that of what we produce, make, or build depends precisely on the quality of our thought” (Richard and Elder 2019, p. 2). Thinking logically, reasonably, and without bias must be systematically cultivated, they argue.
Paul and Elder (2019) define critical thinking as “the art of analyzing and evaluating thinking with a view to improving it” (p. 2). Critical thinking is based on intellectual values that most of us would probably like to cultivate: clarity, accuracy, precision, consistency, relevance, sound evidence, good reasons, depth, breadth, and fairness. Critical thinking requires asking ourselves questions such as: What are my beliefs on a topic? What information am I using to come to my conclusion? What assumptions have led me to this conclusion? From what point of view am I looking at this issue? Does the evidence support my conclusion? What evidence against my hypothesis exists?
That last question is a particularly important one. We are all at times guilty of confirmation bias, a cognitive prejudice where we only seek out or listen to evidence that supports our beliefs. However, critical thinking asks us to seek out evidence against our beliefs, against our hypotheses.
Confirmation Bias
Critical thinking can help us sift through all the sometimes-contradictory information you might find on any given topic. One month, a study might come out showing that wine, in moderation, is good for you. The next month, a study might show that any alcohol consumption is harmful. Within the yoga community, you might hear one teacher say that sitting bones must remain on the floor during a seated forward fold while another might encourage everyone to pull their sitting bones back. See below for a guide to using critical thinking when reading an article about a scientific finding.
The New Yoga Times
Evidence is the available body of facts or information indicating whether a belief or proposition is true or valid. While most people in an asana class are probably not thinking about evidence while flowing through Sun Salutations, many yoga teachers make claims that lack any real evidence regarding the physiological workings of yoga. These claims are also often shared on yoga teacher trainings, on wellness blogs, and in books on yoga. Consider the claim that Shoulder Stand stimulates the thyroid gland or that twists cleanse the liver. Both of these claims are based on speculation, lack evidence, and do not have sound physiological reasoning behind them. Yet, because they are uttered so often, many yogis and teachers begin to consider them fact. But hearing something many times does not qualify as evidence. As philosopher-academic Bertrand Russell wrote, “The fact that an opinion has been widely held is no evidence whatever that it is not utterly absurd” (Russell 1929, p. 58).
Russell also used the analogy of a teapot to illustrate that the burden of proof lies upon a person making unfalsifiable claims, rather than upon others to disprove the unfalsifiable claims. He wrote that if he were to assert, with no proof, that a teapot, too small to be seen by telescopes, orbits the sun in space between Earth and Mars, he could not expect anyone to believe him solely because his assertion could not be proven wrong. It is the same with claims made about yoga.
Russell's teapot
So, evidence is simply knowledge discovered through observation and experimentation, and the best conclusions are drawn from research that has been conducted in a systematic and rigorous way—or, in other words, a scientific way. It is one thing to claim that yoga cures cancer. It is quite another to lead a thorough investigation into the effects of yoga on cancer and cancer patients. The Physiology of Yoga looks at popular claims about yoga, including the claim that yoga is good for cancer patients, and it provides the latest research to determine whether such claims are valid.
Scientists use a hierarchy of evidence (see below) to help assess the quality of research. This hierarchy of evidence is often described as a pyramid, providing a visual representation of both the quality of evidence and the amount of evidence available (Sackett et al. 2000). At the top of the pyramid are systematic reviews, meaning they are both the highest level of evidence and the least common. As you descend the pyramid, the amount of evidence increases as the quality of the evidence decreases. Risk of bias also increases as you descend the pyramid.
Levels of Evidence
Note that editorials, expert opinion and background Information are all at the bottom of the pyramid. This level of evidence includes articles in newspapers or other publications presenting the opinion of the author, or background texts, including textbooks, which provide a broad overview of a topic with a selected review of the scientific literature.
In The Physiology of Yoga, we look mainly at systematic reviews, which are considered a higher level of research. While we searched many scientific databases for reviews on the physiological effects of yoga, this book is narrative in nature and thus is a selected review of the scientific literature. Just as with any review, this book has its limitations.
Good writing should include references, which is why you will find in-text citations with author names and years throughout the book and a reference list at the end of the book. With scientific writing, the reader should be able to track down the same information as the author.
References:
Richard, P., and L. Elder. 2019. The Miniature Guide to Critical Thinking Concepts & Tools. Dillon Beach.
Russell, B. 1929. Marriage and Morals. London: George Allen and Unwin; New York: Horace Liveright.
Sackett, D., S. Straus, W. Richardson, W. Rosenberg, and R. Haynes. 2000. Evidence-Based Medicine. Philadelphia: Churchill Livingstone.