“Now what scientific knowledge is, if we are to speak exactly and not follow mere similarities, is plain from what follows. We all suppose that what we know is not even capable of being otherwise; of things capable of being otherwise we do not know, when they have passed outside our observation, whether they exist or not. Therefore the object of scientific knowledge is of necessity…Now induction is the starting-point which knowledge even of the universal presupposes, while deduction proceeds from universals. There are therefore starting-points from which deduction proceeds, which are not reached by deduction; it is therefore by induction that they are acquired. Scientific knowledge is, then, a state of capacity to demonstrate, and has the other limiting characteristics which we specify in the Analytics; for it is when a man believes in a certain way and the starting-points are known to him that he has scientific knowledge, since if they are not better known to him than the conclusion, he will have his knowledge only incidentally. Let this, then, be taken as our account of scientific knowledge.” – Aristotle, Nicomachean Ethics, VI:3
The problem I have with Aristotle’s conception of science is that, by asserting such an enterprise is driven primarily by deductive reasoning upon observed or inductive premises that do not change, he paints a picture of science that is (1) rarely capable of producing new and interesting findings about the world beyond its starting points, (2) is overly confident in and reliant on starting premises which may be false, and (3) is inconsistent with the induction, falsification, and resulting paradigm shifts essential to advancement in the higher-level sciences.
Firstly, Aristotle states that “…induction is the starting-point which knowledge even of the universal presupposes, while deduction proceeds from universals.” It must be noted, however, that conclusions drawn from a science in which deduction predominates would be inherently bound within the confines of its core axioms, unable to expand much further beyond them. For instance, the statement “All ovals are round, and figure A is an oval, therefore figure A is round” is a deductive one. But rather than allowing us to obtain anything profound about figure A or the nature of ovals and roundness, the conclusions of this syllogism merely fit figure A into the category of roundness by virtue of being an oval, which is innately defined as such anyway.
A second issue with Aristotle’s conception that science only proceeds deductively following its original inductive principles is that such an enterprise would be hugely crippled if its starting points — which may not always reflect universal truth but instead may contain human perceptions conflated with truth — are erroneous. Aristotle takes for granted the fallibility and subjectivity of “starting principles” when he says that “..we all suppose that what we know is not even capable of being otherwise” and historically makes this very error when contending that Earth is the center of the universe based upon a series of premises that, while deductively sound, rely for the accuracy of their conclusion on the faulty initial premise that the Earth appears to be so. If much of one’s worldview is built upon the notion that the Earth is at the center of the Universe (as Aristotle’s was), one may wonder then if once that notion is observed as false, one’s worldview would fall apart entirely.
A related issue is that much of the natural sciences pertain to appearances of which we haven’t grasped the true essence, and it is particularly in these cases where Aristotelian science may fall short. For example, if one induces the starting-point that “All snakes do not have legs,” then many of the fossils which are taxonomically snakes and have actually been shown to have legs, will be incorrectly categorized based on a definitional mistake deductive reasoning will commit on account of its core axiom. Further, whatever one has deduced from the inductive starting-point that “all snakes have legs” will be thrown into question because its foundation was faulty. In this sense, deduction is almost too rigid, and this rigidity — in a world of snakes with potential legs where many things are not neatly defined or necessarily true — constrains our epistemic possibilities and leads us nowhere. Any enterprise of science then, I have shown, aiming to seriously grasp fundamental universal truths, can not proceed solely deductively from an inductive starting point, since any fault of knowledge in said starting point will be assumed as true by the deductive process and invalidate the reasoning that follows. Instead, any attempt at garnering true scientific knowledge must both synthesize one’s experiences and observations into properly generalizable concepts about the world at large and be mindful of the fallibility of inductive starting-points.
My sincere hope that my previous line of reasoning has not made me uncharitable to Aristotle’s conception of science. I merely intend to argue that the modern sciences would not have developed in any meaningful way without an immense amount of induction rather than deduction. This is not to say that the way science has developed to the present moment doesn’t at all reflect Aristotle’s conception of science, but that, since the Scientific Revolution of the 17th century and all modern technology produced thereafter, much of our methods have become more dependent on probabilistic outcomes in which one observes some phenomenon within a sample and generalizes a novel conclusion for the world at large. After all, the theory of quantum mechanics that shook Newtonian physics to its core, or the central dogma of molecular biology that outlined the general processes of all intracellular transformations, were merely inferred because of their explanatory efficacy and in tandem with empirical falsification. In the modern world then, science is not built by an accumulation of deductive knowledge, but instead upon periods of crisis and newly emerging explanations that form paradigm shifts in the field, overhauling even the cardinal principles of past scientific thought in favor of more robust inductions.
In other words, Aristotle’s methods were best suited for a world in which the only tools were the naked eye and the intellect, but as a consequence of our technological prowess, skepticism about the validity of observation and appearances has taken root such that Aristotle’s science can only be conceived of as an ideal in a world without the demon of Descartes. Ultimately, I agree with Aristotle that science, by virtue of being one of the “intellectual parts,” is a discipline concerned with contemplation and truth. Furthermore, I agree that it arises from inductively obtained starting axioms, and that “…the object of scientific knowledge is of necessity,” phenomena that by some universal compulsion have become the way that they are. Nonetheless, where I diverge is in my assertion that such an enterprise in modernity can only produce meaningful, interesting, and novel findings when deductive reasoning is paired (beyond science’s starting points) with inductive inference and empirical falsification; without such tools, mathematics and logic would have been static and unable to give rise to the complex physical, biological, and chemical fields whose central tenets have become reliant on probabilistic inferences and paradigm shifts.