We like to think that science has provided us with descriptive and predictive tools. The world acts in specific, predictable ways. The more we discover the pattern of this predictable uniformity, the more “science” we have. Certainly, we can’t accurately determine the weather at next weekend’s picnic, but we can determine the time of sunrise tomorrow morning, that a particular pool of water will freeze at zero degrees Celsius, that the electron has a charge of minus one, and that every individual shall die.
From where do we derive these “certainties”? They are a product of Inductive Reasoning: we take a specific example, and use our knowledge of the way systems operate to place its behaviour in a more general context. We rely on Inductive Reasoning for every scientific advance and for every meaningful observation of the Universe. Is it, however, any more than a combination of memory and faith: memory of certain patterns in the past, and faith that these patterns will enact themselves again? Certainly, even a shallow thinker can demolish claims that the sun certainly will rise tomorrow: what if a comet smashes into the planet? No planet: no sunrise. What if some freak event in the sun’s core leads to its astonishing extinction? No sun: no sunrise. This is, indeed though, a shallow criticism of Inductive thought, as all it does is to find possible but improbable reasons why a prediction might not be fulfilled. The Inductive Reasoner will then object in turn, claiming that Induction only ever promises probabilistic results. It makes no absolute claims, but can talk about being “reasonably sure” about certain postulations, and even then, only with provisos. Such a proviso might include stating that comments about the certainty of the sun’s rising are to be predicated on there not being undetected comets or undiscovered instabilities in the sun’s core. We can’t find the truth, in other words, but we can make a damn good estimation of it.
For a deeper criticism of Induction, we need to determine the implications of any claim that it operates within a system of probability. Here, we get caught in a circular argument. If something is judged probabilistically, we determine whether it shall recur by fitting its machinations into our current understanding about the uniformity of the universe, and in our belief that certain events will only happen with certain regularity therein. Furthermore, we tacitly accept that nothing fundamental has changed in the Universe to invalidate any further predictions. We’re saying, therefore, that something has a certain probability because, firstly, we have evidence that it has been such in the past and, secondly, we have faith that it shall be such in the future. So, if we say that Induction allows us to find the truth to a certain degree of probability, we’re spinning in a loop – Inductive Reasoning works because.. we have faith in the Inductive Concept of probability which.. requires induction as a “proof”!
Your immediate reaction might be to jump to the Theory of Probability’s defence: in a closed set – for example, with the toss of a coin – surely it is senseless to doubt that getting “heads” in the fair flip of a properly balanced coin shall always be 0.5. Certainly, there’ll be localised pools of improbability (a run of heads or a run of tails) but, averaged out, the universe plays fair, and one should receive heads with a probability of 0.5.
But, again, what is the basis of this Probabilistic certainty? That a balanced small metal disc reacts in a certain way under a predictable gravity field. One knows the way gravity works. One knows the way coins react to being thrown. One can test this empirically, or simulate it. The long-run results are always the same. What room is there for doubt? The answer is: you are basing upon absolutely nothing other than faith your assumption that the universe shall retain its uniformity. Your brain is wired up to find patterns and to guard them jealously. But try to find a reasoned argument why gravity should continue acting the way it has thusfar. Why should the electron retain its charge of minus one? Who gave you that cast-iron guarantee? “Oh, but it has been for billions of years, it’s not going to change now!”. Really? Whence the confidence? One day, I’ll remind you, a Universe suddenly just popped into existence for no particularly discernible reason. At its birth, the rules we take for granted today were nowhere to be found. We might feel in our gut that the Universe is unlikely to change capriciously, but this is nothing more than faith-based hopefulness. We have no rational evidence for this belief. We can count on billions of observations, and millions of predictions, and the models we derive therefrom, but we can never know what tomorrow brings. Maybe gravity has a universal halflife, and is about to turn off. Who knows? Not you. Not anyone. Is it unlikely? You cannot meaningfully say one way or the other. Not until it has happened.
Despite that your mind and gut might suggest otherwise, the universe hasn’t made a pact or bargain with you. Anything can change, just like that, and no prediction is anything more than a hopeful psychological blanket. At the end of the tale of Noah, God promises in His display of the rainbow that He shall never again act in such a randomly destructive manner. The story’s yearning for some Absolute basis upon which to build future civilisations and the discoveries upon which they depend is palpable. “O, Universe”, it seems to cry, “you’ve had your fun – now stop flapping about and guarantee us a bit of stability”. Now, the scientific method and Induction act as our rainbow. But no God is going to make us any promises. We’re just a bunch of superstitious apes mistakenly assuming our little games of spot-the-pattern can give us a God’s eye view of totality. Chicken Little was right: the sky might, indeed, fall down, and nobody can meaningfully suggest otherwise. So, what is a rational soul to do? Seize the day, I suppose, and just enjoy the ride, as trite as it might seem.