When complex arguments are distilled down to single-sentence maxims or sound bytes, applied liberally and without thought to virtually any situation, one will frequently find the salient point bludgeoned and destroyed through misuse. There are a number of examples of this sort of bastardization. For instance, the famed description of evolution as “survival of the fittest” ended up spawning generations of foolish people who thought evolution must therefore be false since overweight dogs exist and not every creature is a beefed-up, muscular man-cake. When a theory is removed of all nuance, having it all strained away through ignorance in the interest of producing a short and sweet description, it is often prime for misuse. As an atheist, one of the most frequently abused phrases of this nature is the old “Absence of evidence is not evidence of absence” argument.

The most annoying thing about this phrasing is that it simply isn’t true at all, whereas at least “survival of the fittest” can be interpreted in a way that accords with evolution. And if one thought about the phrase before actually regurgitating it thoughtlessly, the world would be removed of much unnecessary regurgitation. Suppose, for instance, that there is no apple currently in your mouth. How would you establish the absence of this apple? Ideally, you’d start by attempting to make observations rather than taking the route of faith and asserting that the apple works in mysterious apple-ish ways we cannot comprehend.

Now, if the apple were in your mouth, you’d expect to feel it against your teeth and lips, to obstruct your breathing a bit, to be seen when you look in a mirror, and so on. When you do not make these observations, you conclude on the basis of the lacking evidence that there is no apple in your mouth. In this case, it is quite obvious that absence of evidence is indeed evidence of absence. When you can expect to have evidence of something’s existence, and that expectation is dashed, you can more than adequately deny that the thing exists. So the absence of evidence argument fails, and most making the argument would concede the point.

But if the argument is so flawed, how did it ever attain such massive credibility that it is ingrained in the minds of millions and relentlessly spouted off by any believers in gods, bigfoots, leprechauns, or whatever the hell else crazy people believe? The fact is, there is a grain of truth to the claim. It is, for instance, a logical fallacy to argue from ignorance. In other words, if you are ignorant of the evidence, it doesn’t follow that the evidence does not exist, or that the thing in question is nonexistent. Arguments of this nature are particularly open to question if no attempt at investigation has been made. Someone who shuts his eyes, plugs his ears, and shouts “Na-Na-Na!” when being presented with the evidence for something can very well claim that he has not received any evidence, but in that case it would reflect his willful ignorance of the evidence rather than the nonexistence of the thing in question. (This is a favorite tactic of creationists, for instance, when they blithely assert there are no transitional fossils even as an archaeopteryx bites their ass.)

One of the most important things to note is that though arguing from ignorance is a logical fallacy and obviously precludes any sort of logical certainty, it does not preclude various degrees of certainty or reasonableness. Because we are connected to reality through shoddy, ramshackle sensory apparatuses that are in turn wired to a mass of gray matter prone to delusions, bias, and an overt fondness for comical farting, we unfortunately do not possess any capacity to divine pure and whole truth from our surroundings. Instead, we have to use the much more tiresome process of science, which is really little different from a trial and error heuristic. Anyone who has studied science, for instance, knows that the hypothetico-deductive method is constantly used to assess a theory. Basically, a scientist will don his labcoat, thick-rimmed glasses, and characteristic wild, unkempt hair and proceed to test a theory by inferring what consequences would follow if it were true, and then making observations to see if these consequences truly follow in reality. If the inferred consequences are observed, the scientist shouts, “Eureka!” or “It’s alive! ALIIIIIVVEEEEE!” and the zombie monster he has created proceeds to devour humanity. But here’s the problem. The professor of logic over in the math department might catch wind of this monster creation and deny its validity, because the hypothetico-deductive method as described above is a logical fallacy known as affirming the consequent. So the logician would exclaim, “If theory x entails y, it doesn’t follow that x is true when we see y. Theories w, y, and z could also entail y. You can only DISCONFIRM the theory by observing not-y!” And the logician would keep saying this even as the horrible biological frankenstein devours him.

And that is essentially the problem. In everyday reasoning and the sciences, you don’t expect logical certainty. We are forced to be fallibilists owing to our epistemic limitations, crippling cognitive biases, and obsessive ability to be distracted by bubble wrap. But a person who makes an appeal to the old absence of evidence argument is channeling his inner Cartesian, wishing to go back to a time of rationalism where it was still believed that we could know things with absolute, logical certainty through simple inner reflection. Unfortunately for these little Cartesians, their daily lives are a testament to their disbelief in the rationalist epistemic system. They press the brake pedal expecting their cars to stop, even though there would be no logical contradiction in expecting the car to stop upon jamming on the gas pedal. They also refrain from jumping off of buildings expecting to fly, eating a toaster expecting it to taste like pizza, and reading this blog expecting great remarks of wit and clarifying edification. At heart, we all recognize that the search for logical certainty simply won’t do, and we have to accept that the best we can do is possess varying degrees of certainty, but never complete certainty. What makes our scientific and daily reasoning successful isn’t its certainty, but the fact that it has been tried and tested countless times and worked…so far, at least.

And this is why complex ideas should not be smashed into bite-size, single-sentence nuggets of established wisdom, because it only engenders confusion and breeds misuse. I have managed to write countless blocks of texts in explication of this single sentence, and I feel the need to say even more but halt only out of consideration for my unfortunate readers.

The basic point is that absence of evidence is evidence of absence, provided that we have searched for the evidence and found it lacking. Any sort of objection to this sort of reasoning would necessarily come from an outdated Cartesian point of view that seeks undoubtable, absolutely certain knowledge from pure logical deduction, and it would follow that not only is the absence of evidence not evidence of absence, but also that science is completely erroneous and has nothing of worth to say, and that there are not degrees of knowledge but only black and white, completely wrong or completely right. Most who make such claims about the invalidity of arguments from lacking evidence, of course, do not explicitly deny their daily inductive inferences or the technological and conceptual bounties produced by the “logical fallacy” of science as it affirms the consequent. If they wish to retain this argument, they have to be prepared to lose a lot more than just claims of nonexistence, but virtually any nontautological, empirical claim that can possibly be made!

So, why do I disbelieve in God? Because I’d expect to see evidence of such a being and I do not see evidence of such a being. If one were to respond in a mystical fashion, perhaps arguing that we cannot have knowledge of God, that God transcends us in all ways and resides in some supernatural, unfathomable realm, that would be an adequate criticism, but it leaves the theist on still shakier ground. This “mystical” god, for instance, could not be said to be the creator of the universe, capable of intercession in our daily lives (much less getting nailed to a cross), or capable of any sort of observable act that could be adduced as evidence for its existence. So the theist who makes such an argument should be wary of the qualities and attributes in God he is necessarily giving up in doing so, as they likely conflict with the tenets of his religion. Of course, this also opens up another avenue of attack against belief in such a God. The atheist would need only point out that if God is being defined as some unknowable, ineffable entity, that the theist could not possibly know what it is he is saying to exist. He may as well be muttering an incomprehensible gurgle. It is as if I told someone a parrot is on my shoulder, and upon being questioned about the lacking evidence of any parrot, asserting that it is a mystical, unknowable parrot, at which point I am asked how I could know it is parrot-like or know it is on my shoulder if it is indeed unknowable and so deeply mystical, to which my only response is, of course, an incomprehensible gurgle. The principle of Ockham’s razor also serves to adequately refute any appeals to mystical, completely unobservable gods. One should only posit additional existential entities if there is additional evidence for these entities, and naturally atheism is a more parsimonious explanation for lacking evidence than a needless hypothesis about an unknowable God existing. And don’t even get me started on how badly the principle of Ockham’s razor is abused. Ockham’s trusty razor has been abused so many times it will in all likelihood grow up to engage in sexually deviant behavior and suffer sever posttraumatic stress disorder.