The nature of scientific experiment, as part of scientific method, has been and continues to aim at making testing as ‘pure’ as is possible. This is to say that when an experiment is to be carried out, then as many extraneous items of circumstance and presence surrounding the setting of it up are attempted to be eliminated.
Any condition or item extraneous to the composition and nature of the theory that is being tested is attempted to be taken away from it making interference with the course of the experiment.
When things are not able easily to be taken away, and they are extraneous and so not useful or pertinent to the testing of the theory in question, they are attempted to be neutralised or isolated in some way so that their effects of being present do not influence or alter inconveniently the results (expected) of a test.
When such things are not able to be taken away and also are not able easily to be neutralised or else isolated, then their influences or interferences with the procedure of an experiment and so with its (expected) results is attempted to be allowed for in the anticipated results of a test. This is done so that a result of a test is able to be evaluated and then adjusted by allowing for the disorder or the unbalancing of an initial result by the interference of extraneous items or conditions unable to be removed beforehand from the proceedings of a test.
And so the ‘ideal’ experiment is one which would take place making use only of the essential ingredients needed to run a bona fide authentic test – the sufficient and necessary items only, with all other items and conditions expelled from having an influence on the outcome.
The nearest scientists come to this ‘pure’ or ‘ideal’ situation for doing experiments is when they conduct what are known as ‘thought experiments’. Thought experiments are done when scientists think-through a set of circumstances and the interactions of those circumstances, so as to try to find a logical or other valid outcome, but crucially without their using physical apparatus or materials. Thought experimentation is done wholly in the head.
The general nature of doing experimentations in these ways then necessitates that tested and established theories of science are expected to align themselves most conformably with the results and outcomes of new experiments. They are to align as being the science and its precepts whose reliability supports the new tests’ probability and probity for success, as well as providing their likelihood in being selected for trial in the first place. But all new tests are attempted, as far as this is possible, within a pure and ‘sanitised vacuum’ so to speak.
There might be such things as complex theories to be tested, or experiments which involve more than one theory to be tried, or else one or more established theories might be included as given parts of the set up model so as to support the conditions for experiment on proposed theory to be tested.
But the basic proposal holds good always; that all else which is unnecessary and extraneous to a proposed test is to be removed, neutralised or taken account of so as to get a result from the test that is as far as possible a ‘pure’ result, unadulterated as if existing in an ‘sanitised vacuum’.
The first thing to make a note of about this methodology is that even in the most ‘pure’ environments of experimentation, in the ‘thought experiments’, there is much scope for interferences and for extraneous items to intervene regardless in a ‘proper’ procedure.
The historical case of is the postulation of a gas called phlogiston. This gas was assumed to be of negative mass, and being thought such was thought accountable for the loss of mass witnessed in burnt ashes when compared with the mass of the items which were burnt, before their burning. There was involved in this supposed solution phlogiston a thought experiment which took the results of a physical experiment and misconstrued them by creating the concept of phlogiston. The interpretation of the findings was flawed, and was flawed for two reasons.
Firstly there was most likely insufficient circumstantial understanding of science available to and surrounding the creator of the concept of phlogiston. Such a lack in great part allowed opportunity for the creator of that concept to postulate a gas which had properties unlike any other comparable material then known or understood.
Secondly the reasoning of the creator of the concept of phlogiston seems to have opted for ‘the glass half empty’ choice over and above the ‘glass half full’ choice.
Like in solving x in a quadratic equation there can be a negative answer and a positive one; only the positive one being of actual use in a practical application, to say an engineering project. The concept of phlogiston seems to have arisen as if an engineer was working to apply negative loads or stresses to an idea for a building he was planning.
The conceptualiser of phlogiston had not supposed that materials had left the ash, and they were at one time part of its mass, but at a time beforehand, when they were part of the material before it burnt to ash. Instead he had opted for the nearest best alternative; that a gas of negative mass had been added to the materials during combustion, thus making their ash measure less in mass.
The lack of sufficient basement scientific understanding was the open gate through which the conceptualiser of phlogiston was able to walk though into a fallacious belief.
The simple truth is that an experimenter has to be able to have foreknowledge of the presence and the nature of all extraneous items and conditions which could present themselves and so might have potential to interfere with an experiment he is proposing. In this way he hopes to obtain a ‘pure’ state for the test’s performance. And the case with phlogiston implies to us that even were this first obstacle overcome and a ‘pure’ state was made possible in which to test a theory, there might still remain pitfalls in the mind and in the reasoning of men and women which might intervene to cause an interpretation made wrongly from any perceived empirical result.
The misinterpretation of observed phenomena is an accidental and incidental occurrence however, and as such is harder to guard against than safeguards made by using one’s sound basement understanding of all the science one feels assured of, and so before the case eliminate as far as possible from a test interferences . This second demand requires only diligence and application; the first demand, for correct interpretation of observed results, might truly be wholly unluckily mistaken in certain unfortunate cases.