In an earlier essay, I promised to write a summary of the book by Prof. Claude Bernard. In fact, it appears that I have to write more than one essay to bring out as many points as possible. I sincerely hope that those of you interested in biological research will read this classic published originally in 1865. The points Prof. Barnard makes in this book are as important today as when he made them.
Prof. Bernard starts the first chapter by stating that experimental method consists of the art of investigation and the art of reasoning. The art of investigation seeks to establish facts. The art of reasoning works on the observed facts logically in the search for truth. In his own words: "Observation, then, is what shows facts; experiment is what teaches about facts..."
There are three phases to experimental knowledge: making an observation, comparison with established data and coming to a conclusion. One can observe nature and gain experience, which is empirical and based on unconscious reasoning. This is subject to errors such as incomplete observation, personal bias etc. The other method is experimental, based on "getting accurate facts by means of rigorous investigation" and working them up with careful experimental reasoning. He defines experimental reasoning as always dealing with two facts at a time: "observation, used as a starting point; experiment used as conclusion or control".
The next major point he makes is that in scientific investigation, "minutiae of method are of the highest importance". He then differentiates passive observation from experimental observation. In experimental observation the scientist "acts on matter, analyzes its properties and to his own advantage and brings about the appearances of phenomena which doubtless occur according to natural laws, but in conditions which nature often has not achieved". In other words, experiment is "induced observation".
The experimenter who is the observer in the experimental method must possess two qualities in his quest for truth. He must submit his ideas (his hypothesis) to the control of facts and must make sure that the facts which are the starting point for further reasoning are accurate and well-established. He must put to nature all sorts of questions to test various hypotheses which suggest themselves and "as soon as she speaks, he must hold his peace". He must "never answer for her, nor listen partially to her answers by taking, from the results of an experiment, only those which support or confirm his hypothesis". "He must submit his idea to nature and be ready to abandon, to alter or to supplant it, in accordance with what he learns from observing the phenomena which he has induced".
In the final section of Chapter 1, Prof. Bernard defines a true scientist as one who notes a fact and gets an idea in his mind based on this fact. Then, using his reason and imagination he devises an experiment to bring about the conditions to test this idea. He observes the new phenomena brought out by the experiment, gets to the next step of reformulating his hypothesis based on the new facts and so on. "The mind of a scientist is always placed between two observations: one which serves as a starting point for reasoning, and the other which serves as a conclusion".
Accurate facts are absolutely necessary. But, it is the experimental reasoning that builds up science. "The idea is what establishes, as we shall see, the starting point or the primum movens of all scientific reasoning, and it is also the goal in the mind’s aspiration toward the unknown".
(To be continued)
An Introduction to the Study of Experimental Medicine. Prof.Claude Bernard. Translated by H C Green Dover Publications Inc. 1957