As I've said many times, a guiding light of mine is the simple proposition that words mean things. Tossing verbiage around without thought or care, then taking that same word-tossing to the next level and insisting that, Humpty Dumpty like, we can just make words mean whatever we wish, well, that's enough to make me wonder about sanity.
For several years now, reading various places around the Internet, the phrase "reality-based community" has been bandied about, not only as a counter to Karl Rove's "We're an Empire, we create our own reality," nonsense. The meaning of the phrase has expanded to include the claim that science deals with "reality" and religion, well, to quote a commenter at the science blog Pharyngula, "begins with bullshit."
"Reality" is a word I detest. Like "morality", and "truth", and "belief", and "nature", the word has become unhinged from any reference point. Does it mean our common, everyday experience of the flow of space-time? Does it refer to the mathematical equations that demonstrate how matter and energy are, at a basic level, interchangeable? Does it refer to the flow of human events that we, being human, privilege over many other events? One could go on asking questions of this sort, and I confess they all sound a bit pedantic, but the point, I hope, is clear. That which we call "reality", at least in our mundane sense, is by and large a facade, a construct of our human sense organs coping with a variety of inputs and attempting to make sense of those inputs in a way that maximizes our survival advantage. Were to have, say, the olfactory abilities of some dogs or carrion-eaters, say, the world would be "real" in a fundamentally different way than it currently is to us. If we had the ability some snakes do, to "see" heat emissions, our "reality" would be a very different thing indeed.
With the help of several different branches of science, we have come to learn over the past century or so that what we call "reality" or "the physical universe" is not at all what or how it appears. Indeed, "physical" is hardly what I'd call any particular object that has mass, considering even the most dense elements and objects are still, by and large, empty space. In the early decades of the 20th century, physicist Niels Bohr (who counts Olivia Newton-John among his grandchildren) developed a model of the atom, what was once considered the most basic unit of physical matter, that looked quite a bit like a solar system. Around the central nucleus, which consists of neutrons and protons (positively charged particles) there swirl various layers of electrons (negatively charged particles; and please note, "positive" and "negative" are conventional designations rather than describing anything inherent in the particles themselves).
The problem with the model was, no one had ever seen an electron. By the time the First World War was over, there had been enough experiments working on the mass of atomic nuclei and their constituent parts to get a rough approximation of the masses of both protons and neutron. In theory, the neutron was a particle with no charge that was, in fact, a proton and an electron fused together. Except, the difference in mass between the proton and neutron was almost statistically negligible.
Furthermore, while it was easy enough to follow the effects of what were supposed to be electrons, it became increasingly apparent the particles themselves were probably beyond anyone's capability of "discovering" in a conventional sense.
In the 1920's, Werner Heisenberg went a bit further. Studying elementary particles - the stuff that was discovered to make up protons and neutrons and electrons - Heisenberg made the claim that, for all intents and purposes, such things didn't actually exist. The equations made clear they should exist. The experiments constructed to demonstrate the correctness of the equations were then and continue to be consistent within striking orders of magnitude. Yet, no one has ever, nor probably will ever, see a boson or a meson or, God help us all, a graviton. First of all, one of the consequences of General Relativity is that energized particles behave both as objects containing mass and also as energy waves. There are packets of light energy called photons, yet light also behaves much the same way waves do - with amplitude and frequency. Heisenberg stipulated, further, that while it was well enough to give the equations their due, since they were confirmed by experiments, it was probably better to let the paradox rest and act as, for the sake of any particular experimental procedure, these particles exist. It is a position that is known as "operationalism": we cannot know whether or not there "really" are "things" out there we call elementary particles, since the only confirmation we have of their existence are particular scientific tests that in themselves only demonstrate that certain events happen, rather than there are any such "things" in and for themselves.
Erwin Schrodinger, in a famous complaint aimed at Heisenberg, said that operationalism, combined with Heisenberg's more well-known position that we cannot know both the position and momentum of an elementary particle, led to the paradox of the cat in the box. The cat was both alive and dead, Schrodinger said, under Heisenberg's working theories. To which Heisenberg replied, "True enough. Until we open the box to find out whether or not the cat is dead." Without observation, the propositions, "The cat in the box is dead," and, "The cat in the box is alive," have an equal chance of being accurate.
Another part of quantum mechanics that makes a mockery of "reality" is the idea that a quantum event somewhere here on earth has a direct and measurable effect upon a quantum event in a star in the Horsehead Nebula. Known as quantum entanglement, it is the proposition that, against any classical ideas of what was known as "local reality", action-at-a-distance (which Einstein, whose theories led to this and a host of other issues he didn't like, called "spooky") was a basic part of the physical make-up of the Universe. For years, the position set out by Einstein and some colleagues that this unacceptable state of affairs showed that quantum mechanics was incomplete held sway. In 1964, John Stewart Bell proposed that, in fact, what was known as the Einstein-Rosen-Podolsky paradox was in error, and, in fact, over the course of a series of trials, there was an increasing probability of determining how two seemingly unrelated quantum events were, in fact, related.
Now, many physicists chuckle when the positions taken here - that there is an inherent nothingness to reality; that there is an inherent unpredictability to reality; that an event at point (a), without either any time lag or physical contact, can influence an event at point (b) - are expanded in various fictional settings. Most even the most well-versed scientists would insist these phenomena are highly localized and specialized. Just because we cannot know both the position and momentum of an elementary particle does not mean Schrodinger's cat is both alive and dead until we open the box to investigate, they say. Schrodinger, it seems, made a category mistake (no pun intended).
To an extent, this is a perfectly sound argument to make. After all, I wouldn't think of trying to shove my head through a wall, even though I know both the wall and my head are mostly empty space.
Which position, of course, begs many questions, not the least of them being: What is reality? It might well mean our everyday reality we encounter. Yet, again and again, it was precisely scientific investigation of that everyday reality that revealed the paradoxes discussed above. Which leaves me asking, again, what is reality? Would it be possible to operate as if quantum mechanics governed our macro-world? Of course, in some ways, it does. If you're reading this on a computer, you can thank quantum mechanics for that.
Back in the early 1990's, philosopher Jonathan Searle wrote a longish book entitled The Philosophy of Mind. Over and over in that book, Searle repeated that reality is and I quote, "elementary particles in fields of force." While this might well be a good working definition in some circumstances, the fiction that the word "particle" creates - that there are these "things" out there we call elementary particles, rather than energy traces from collisions that fit with mathematical predictions concerning the behavior of small masses of light elements colliding at near the speed of light - renders this "definition" of "reality" untenable (there are a host of other issues with Searle's book, but this one always nagged at me). In fact, while we may be able to express, with a certain degree of confidence, through certain mathematical equations, the statistical regularity of certain events (without ever being able to approach precision on all such events; more precision one way leads to less precision the other), this hardly means we understand what the word "reality" means, or to what it refers.
When I read people talking about how they're so scientific and are part of the reality-based community, I figure they flunked Physics 101. Because if they're relying on science for their understanding of reality, then they have some problems.