Once in a while I hear or read about dogmas as if they were models. I came to realize that some people might not be aware what a dogma is and before the (mis)use of this word spread even further, I hope you will agree to get it back into its original meaning.
The Oxford dictionaries define dogma as “A belief or set of beliefs held by a group or organization that others are expected to accept without argument”. Other dictionaries report similar definitions, but the Merriam-Webster also include the slightly softer “Something held as an established opinion, especially a definite authoritative tenet”. Many dictionaries also report to religious doctrines. Therefore, dogma can’t be used as synonym of model or hypothesis, particularly in science. Of course, most people are still using the word dogma correctly even in science, to refer to a model that has become established fact despite no, weak or even erroneously interpreted evidence for it.
I suspected that most of the damage has been caused by Francis Crick when he has introduced the “Central Dogma ” of molecular biology. Let’s be clear, I do not want to be pedantic and I care very little about semantics, but the correct use of the words dogma, hypothesis, model, theory, is rather important in science. There are instances when these four words might be interchanged but we should – I hope – all agree that dogma is to be used only with a negative connotation (in science).
I assume you know what the central dogma is but if you do not, the Wikipedia page is good enough to get an understanding. In lectures during the late 50s, Francis Crick stated that “Once information has got into a protein it can’t get out again” and named this statement “The Central Dogma”. Apparently the name was a bit of a joke, as it appears evident from the famous document stored by the Wellcome Library. The initial paragraph was entitled “The Doctrine of the Triad”, a clear reference to DNA, RNA and proteins with a rather obvious analogy to the Christian doctrine of the Trinity.
I must admit I did not read Crick’s autobiography, but it is well known that there, he writes that “I called this idea the central dogma, for two reasons, I suspect. I had already used the obvious word hypothesis in the sequence hypothesis, and in addition I wanted to suggest that this new assumption was more central and more powerful.” and “As it turned out, the use of the word dogma caused almost more trouble than it was worth. Many years later Jacques Monod pointed out to me that I did not appear to understand the correct use of the word dogma, which is a belief that cannot be doubted. I did apprehend this in a vague sort of way but since I thought that all religious beliefs were without foundation, I used the word the way I myself thought about it, not as most of the world does, and simply applied it to a grand hypothesis that, however plausible, had little direct experimental support.”
Then, I asked a friend who lived those times if perhaps the word dogma was used slightly differently in the past and I got this brilliant response: “A dogma in science is a fanatic intrusion into rational thought. When a big name in science makes a joke, accolades of small names taking it seriously are sure to follow… A model becoming a dogma is ready for the bin. Never had a dogma crossing my path.”
Well, nowadays I do see dogmas crossing my path but never mind, that is a different story. For the young students who might read the “central dogma” in text books and then adopt the term “dogma” as equivalent to model or hypothesis then, just two suggestions.
First, a scientists should be always skeptical and doubt about anything. It is unavoidable that sets of established facts, sometimes even wrong, become generally accepted in a discipline and crystallize into a real dogma that no one challenge. However, it is our duty to challenge any interpretation, any model, whenever is conflicting with evidence.
Second, let’s reserve the word dogma (in science) to critically identify established believes with insufficient or contradictory experimental evidence, or perhaps for jokes…
Ironically, the “Central Dogma” was a very good hypothesis.
