3. Observation, Theory, and Prediction
Science relies on quantifiable observation of material objects as its starting point and its source of data. These data are then summarized in statements which we collectively call theory. The phrase “It is just a theory” does not apply to scientific theories, because the latter are the outcome of a large number of quantitative observations and experiments and have been confirmed by an equal number of tests. At the early stages of the development of a theory, various conjectures, models, or hypotheses may have been proposed. But once the statement is christened as “theory,” it acquires a permanence that is not even remotely shared by “just a theory.”
Not every quantifiable observation is scientific. Neither counting the number of cars crossing an intersection to find the traffic pattern of that intersection, nor contacting people to gather “data” about voters’ behavior is a scientific observation. Observation in science is either prompted by a theory, in which case it becomes a test of that theory, or is performed with the intention of discovering a secret of nature. Because physics, chemistry, and molecular biology all deal with atoms and molecules,
The instruments used for observation are very similar in the three branches of science.
A theory explains the existing observational data for which it is designed. But if it stopped there, it would not deserve to be called a “theory.” The third characteristic of science is that its theories predict new results that are numerical and could be proven wrong. A statement like “Santa Claus exists, but whenever a skeptic tries to find him, he vanishes into another dimension.” cannot be proven wrong. It is not falsifiable.
Prediction, numerical prediction – risky prediction as Karl Popper so aptly called it – is one of the most significant characteristics of science which distinguishes it from pseudoscience.
For pseudoscience, such as psychoanalysis, every occurrence is a confirmation of the theory, because the theory is reinterpreted retrospectively so that the new interpretation accommodates the new occurrence. A pseudoscientific “theory” is not falsifiable. In contrast, the general theory of relativity, for example, predicts the bending of star light in the gravitational field of the sun, and gives an exact value for this bending. If observation confirms this numerical value, the theory stands; if it doesn’t, the theory falls. This is what is meant by falsifiability.
The time lapse between the creation of a theory and its predictions could vary considerably. Einstein’s general relativity predicted the bending of light in a strong gravitational field almost at the same time as it was proposed, while it took several years before it predicted the big bang. Similarly, it took many years before the predictive power of the double-helix was fully appreciated.
A scientific theory, once proposed and proven experimentally, becomes detached from the person who created it. There is no mark of the personality of the theorist on the theory, and scientists do not go back to the original article as an “authority.” Erwin Schrödinger wrote his equation in January 1926. The equation had a “psi” function, which no one knew how to interpret. When in June 1926 Max Born correctly interpreted the function as probability (amplitude), an uproar emerged in the physics community opposing such an interpretation. Schrödinger was one of the fiercest opponents of this interpretation. Nevertheless, Max Born was right, and ever since June 1926, the Schrödinger equation no longer belonged to Schrödinger! It was completely detached from him and took a life of its own.
A scientific theory is completely detached from the scientist who proposed it and future scientists don’t go to the original article as an “authority.”