As part of their efforts to keep us believing that we live in a bland universe (what we might call a three-flavor universe), and not a funky universe rich in paranormal phenomena (what we may call a 64-flavor universe), various people engage in what we might call anomaly denial. Such figures tend to repeat the same lame excuses and catchphrases again and again, to try to dismiss strange observations that don't fit in with their tidy sanitized worldviews. Let's look at some of these catchphrases, and see why they are mainly just vacuous rhetorical devices.
“Things like that don't happen.”
This is such a sweeping dogmatic statement that it can be immediately dismissed as an overreaching absurdity. Not only does the statement claim that some particular type of anomalous phenomena doesn't occur, it basically asserts that no paranormal phenomena ever occurs. One way to rebut the claim is to remind someone that the universe began in the most anomalous, unusual way imaginable (according to scientists, the universe suddenly burst into being from an infinitely dense point). Then say: “Things this odd apparently have been happening from the very beginning of time.” Another good rejoinder to the claim “things like that don't happen” is merely to ask: how do you know?
“There must be a rational explanation.”
This is basically a rhetorical device that attempts to characterize any paranormal explanation as irrational, and then asks us to look for mundane explanations that are deemed rational. A good way to counter this bit of rhetoric would be to say something like, “Yes, everything in the universe has a rational explanation, even the most mysterious things that are utterly beyond human explanation.”
“If this existed, scientists would understand it or acknowledge it.”
One reason that this claim is not very persuasive is that the universe is full of mysteries that scientists don't understand, such as the Big Bang, dark energy, dark matter, and quantum entanglement. Another reason that this claim is not very persuasive is that investigating the paranormal seems to be almost a cultural taboo for the great majority of scientists. Since most scientists have pretty much declared a “hands off” policy in regard to the paranormal, there is no reason why we should expect them to understand anything relating to the paranormal, even if it existed. Similarly, if I refuse to look into the topic of quantum chromodynamics, you should not expect me to understand it.
“You don't believe in that kind of nonsense, do you?”
This is a kind of loaded question similar to a question such as, “Have you stopped beating your wife?” The person who asks the question hopes that the person will answer, “No,” and thereby exclude the paranormal possibility. But if the person answers, “Yes,” he is then put in the position of asserting his own belief in nonsense.
A good reply this type of question is to say something like: it's illogical to deny the possibility of something when evidence for such a thing appears.
“I can't believe that – it's impossible.”
In general, science does not warrant claims that particular anomalous phenomena are impossible. Almost the only claims that are impossible would be those that assert the nonexistence of something science has proven. So claims such as “carbon doesn't exist” or “gravity doesn't exist” are impossible, according to science. But science in no way excludes most of the anomalous phenomena people claim to have observed.
“I have to reject that report – it's unscientific.”
Some may think that it is real scientific to immediately reject some report or claimed observation that does not match the expectations of scientists. But that usually isn't scientific, but instead the opposite of scientific. A good scientific procedure is to accept any observation or possible observation relating to a hypothesis, and to store that observation in a set of observations that will be considered whenever that hypothesis is to be considered. You could describe such a policy with this slogan: bank it, don't bunk it. In other words, rather than immediately dismissing an anomalous observation with some lame excuse such as “things like that don't happen,” you should “bank” an observation by putting it somewhere where it might be “withdrawn” for further scrutiny when the topic is under further analysis.
“There's no evidence for that.”
This is perhaps the favorite catchphrase of skeptics, and is ruthlessly deployed even in many cases where there is a huge amount of evidence for something. The best way to counter this (when appropriate) is to assert the opposite, something like: “To the contrary, there is a great deal of evidence for this.”
“You must have just hallucinated.”
Variations: “He must have just hallucinated” or “She must have just hallucinated.”
This catchphrase is useful for trying to wipe out evidence for various anomalous phenomena such as apparitions, near-death experiences or UFO's. You can rebut it by pointing out that hallucinations can reasonably be attributed only to people with chronic mental illnesses or people under the influence of alcohol or drugs, and cannot be reasonably attributed to people who are in a deep state of unconsciousness. I am using here the proper definition of hallucination: an apparent perception (such as seeing something or hearing something) that comes without any external stimulus that produces it.
“Your eyes must have been playing tricks on you.”
This is an appeal to what is basically a bogus possibility, the possibility that your eyes suddenly malfunctioned, and caused you to think you were seeing something that you weren't seeing. Since the human eye is a remarkably reliable instrument, this isn't a believable rejoinder. Unless you have chronic vision problems, your eyes will never “play tricks on you,” although your mind may misinterpret some information that your eyes send you.
“Your camera must have malfunctioned.”
This is like the “your eyes must have been playing tricks on you” statement, but involves a camera rather than an eye. It's just as weak a statement, because modern digital cameras are very reliable things that virtually never have one-shot malfunctions that might be interpreted as evidence for the paranormal.
“It was probably just an optical illusion.”
If you think an optical illusion is a plausible explanation for an anomalous observation, ask yourself: when was the last time you can remember seeing an optical illusion? It's probably some optical illusion you saw in a book. That's because optical illusions are pretty rare in nature.
“People like me don't believe in that kind of stuff.”
Variation: “People like us don't believe in that kind of stuff.”
This is basically an appeal to a sociological or cultural taboo. The person using the catchphrase is basically reminding you that within some particular subculture, there are penalties or sanctions for believing in something like the anomaly being considered. A rejoinder is to point out that acceptance of an anomaly should be based on evidence, not on taboos.
“That is too weird to be real.”
Variation: “That is too crazy to be true.”
One can counter this catchphrase with this observation: nature loves weirdness. And, of course, it does. Almost all of the things that might be dismissed as “too weird to be true” are not half as weird as some of the things scientists believe in, such as the weird rules of quantum mechanics, quantum entanglement, black holes, neutron stars, and the sudden origin of the universe in a singularity.
“They're all just a bunch of fakers.”
Using any statement beginning with “they're all just...” is in general a sign of prejudice and stereotyping. It's generally impossible to prove such statements, and it's also generally impossible to prove weaker statements beginning with “they're mainly just a bunch of ...”
A good way to rebut such bigotry is just to ask: what evidence do you have to support that statement?
“It was probably just a lens smudge.”
When used to dismiss some anomaly photograph, a comment such as this is basically equivalent to accusing the photographer of being a complete moron. Lens smudges keep producing the same effect until the camera is cleaned. Only the most careless and dimwitted photographer would fail to notice that such an anomaly was occurring in each photo. Also, lens smudges cannot be used to explain anything other than a blurry blob, because the camera cannot focus on anything on the lens.
“It was probably just dust.”
Dust isn't big enough to produce photographic anomalies when a photographer shoots in ordinary air. The particle sizes of outdoor dust particles are only about 1 micron, which is about one fifteen thousandth (1/15000) of the area right in front of the lens. That's hundreds of times too small to produce a decent photographic anomaly. If the dust in ordinary air were sufficient to produce photo anomalies, almost every flash photo would show such anomalies.
“It was just a cosmic ray hitting the camera.”
This excuse is used to explain away anomalies in photos taken in space or on Mars. It isn't a very persuasive excuse when the anomaly occurs on the exact horizon or when the anomaly seems to have more structure than we would expect a passing cosmic ray to produce.
Below is an example of a anomaly explained as a "cosmic ray hit." We see what looks like a luminous figure. The original NASA photo can be seen here. The figure appears exactly in front of the landing site where one of the Mars rovers was deployed from. What are the odds against a cosmic ray hitting in that exact spot, to create what looks like a figure with legs?