Recently, my attention was drawn to an article by Pascal-Emmanuel Gobry, on The Week website, telling the world what the real meaning of ‘science’ is (h/t Peter Broks @peterbroks). According to Mr Gobry science is the process through which we derive reliable predictive rules through controlled experimentation [his emphasis]. This definition is of course totally inadequate but I’m not going to try and correct it in what follows; I gave up trying to find a simple all encompassing definition of science, a hopeless endeavour, a long time ago. However Mr Gobry takes us on a whirlwind tour of the history of science that is to say the least bizarre not to mention horribly inaccurate and in almost all of its details false. It is this part of his article that I’m going to look at here. He writes:
A little history: The first proto-scientist was the Greek intellectual Aristotle, who wrote many manuals of his observations of the natural world and who also was the first person to propose a systematic epistemology, i.e., a philosophy of what science is and how people should go about it. Aristotle’s definition of science became famous in its Latin translation as: rerum cognoscere causas, or, “knowledge of the ultimate causes of things.” For this, you can often see in manuals Aristotle described as the Father of Science.
The problem with that is that it’s absolutely not true. Aristotelian “science” was a major setback for all of human civilization. For Aristotle, science started with empirical investigation and then used theoretical speculation to decide what things are caused by.
What we now know as the “scientific revolution” was a repudiation of Aristotle: science, not as knowledge of the ultimate causes of things but as the production of reliable predictive rules through controlled experimentation.
Galileo disproved Aristotle’s “demonstration” that heavier objects should fall faster than light ones by creating a subtle controlled experiment (contrary to legend, he did not simply drop two objects from the Tower of Pisa). What was so important about this Galileo Moment was not that Galileo was right and Aristotle wrong; what was so important was how Galileo proved Aristotle wrong: through experiment.
This method of doing science was then formalized by one of the greatest thinkers in history, Francis Bacon.
Where to start? We will follow the Red King’s advice to Alice, “Begin at the beginning,” the King said, very gravely, “and go on till you come to the end: then stop.”
Ignoring the fact that it is highly anachronistic to refer to anybody as a scientist, even if you qualify it with a proto-, before 1834, the very first sentence is definitively wrong. Sticking with Mr Gobry’s terminology Aristotle was by no means the first proto-scientists. In fact it would be immensely difficult to determine exactly who deserves this honour. Traditional legend or mythology attributes this title to Thales amongst the Greeks but ignores Babylonian, Indian and Chinese thinkers who might have a prior claim. Just staying within the realms of Greek thought Eudoxus and Empedocles, who both had a large influence on Aristotle, have as much right to be labelled proto-scientists and definitely lived earlier than him. Aristotle was also by no means the first person to propose a systematic epistemology. It would appear that Mr Gobry slept through most of his Greek philosophy classes, that’s if he ever took any, which reading what he wrote I somehow doubt.
We then get told that Aristotelian “science” was a major setback for all of human civilization. Now a lot of what Aristotle said and a lot of his methodology turned out in the long run to be wrong but that is true of almost all major figures in the history of science. Aristotle put forward ideas and concepts in a fairly systematic manner for people to accept or reject as they saw fit. He laid down a basis for rational discussion, a discussion that would, with time, propel science, that is our understanding of the world in which we live, forwards. I’m sorry Mr Gobry, but a Bronze Age thinker living on the fertile plains between the Tigris and the Euphrates is not coming to come up with the theory of Quantum Electro Dynamics whilst herding his goats; science doesn’t work like that. Somebody suggest an explanatory model that others criticise and improve, sometimes replacing it with a new model with greater explanatory power, breadth, depth or whatever. Aristotle’s models and methodologies were very good ones for the time in which he lived and for the knowledge basis available to him and without him or somebody like him, even if he were wrong, no science would have developed.
Gobry is right in saying that the traditional interpretation of the so-called scientific revolution consisted of a repudiation of Aristotelian philosophy, a point of view that has become somewhat more differentiated in more recent research, a complex problem that I don’t want to go into now. However he is wrong to suggest that Aristotle’s epistemology was replaced by reliable predictive rules through controlled experimentation. Science in the Early Modern Period still has a strong non-experimental metaphysical core. Kepler, for example, didn’t arrive at his three laws of planetary motion through experimentation but on deriving rules from empirical observations.
Gobry’s next claim would be hilarious if he didn’t mean it seriously. Galileo disproved Aristotle’s “demonstration” that heavier objects should fall faster than light ones by creating a subtle controlled experiment (contrary to legend, he did not simply drop two objects from the Tower of Pisa). Aristotle never demonstrated the fact that heavier objects fall faster than light ones; he observed it. In fact Mr Gobry could observe it for himself anytime he wants. He just needs to carry out the experiment. In the real world heavier objects do fall faster than light ones largely because of air resistance. What Aristotle describes is an informal form of Stokes’ Law, which describes motion in a viscous fluid, air being a viscous fluid. Aristotle wasn’t wrong he was just describing fall in the real world. What makes Gobry’s claim hilarious is that Galileo challenged this aspect of Aristotle’s theories of motion not with experimentation but with a legendary thought experiment. He couldn’t have disproved it with an experiment because he didn’t have the necessary vacuum chamber. Objects of differing weight only fall at the same rate in a vacuum. The experimentation to which Gobry is referring is Galileo’s use of an inclined plane to determine the laws of fall, a different thing altogether.
We now arrive at Gobry’s biggest error, and one that produced snorts of indignation from my friend Pete Langman (@elegantfowl), a Bacon expert. Gobry tells us that Galileo proved Aristotle wrong: through experiment. This method of doing science was then formalized by one of the greatest thinkers in history, Francis Bacon. Galileo’s methodology of science was basically the hypothetical deductive methodology that most people regard as the methodology of science today. Bacon however propagated an inductive methodology that consists of accumulating empirical data until a critical mass is reached and the theories, somehow, crystallise out by themselves. (Apologies to all real philosophers and epistemologists for these too short and highly inadequate descriptions!) These two epistemologies stood in stark contrast to each other and have even been considered contradictory. In reality, I think, scientific methodology consists of elements of both methodologies along with other things. However the main point is that Bacon did not formalise Galileo’s methodology but produced a completely different one of his own.
Apparently Mr Gobry also slept through his Early Modern Period philosophy classes.