My students know that I have very mixed feelings about Wikipedia. On the one hand, it can be invaluable for quickly obtaining or checking uncontested facts about names, dates, locations, and sequences of events. It can also be a useful starting point for research; it often provides a serviceable orientation to a topic and can point you to some useful sources. Even so, Wikipedia can be desperately unreliable and biased when it comes to controversial issues and even some matters that shouldn’t be controversial. (I have a folder on my computer named ‘Wikidpedia’ where I collect particularly egregious examples.) It’s well known that the ‘community’ of Wikipedia editors is ideologically skewed compared to the general population, such that some topics simply cannot be represented in a balanced and responsible fashion (see here for one embarrassing example).

Anyway, I recently came across an almost laughable case of Bad Wikipedia. For reasons I don’t remember now, I found myself consulting the entry on ‘Reality’ (insert your own punchline here). Here’s how the article began:

Reality is all of physical existence, as opposed to that which is merely imaginary. It is the name for all of physical existence, but the word is also used in a declension to speak of parts of reality that include the cognitive idea of an individual “reality” (i.e. psychology), to a “situational reality,” or a “fictional reality.”

The term is also used to refer to the ontological status of things, indicating their existence, but this is simply the idea of giving names to smaller “realities,” and seems vague and academic without the idea of physical existence as the first “reality,” and the others being smaller parts.

This is awful in so many ways. In the first place, it defines reality as physical existence, and contrasts physical existence with the “merely imaginary.” In other words, it’s a metaphysically prejudicial definition that assumes physicalism, the view that only physical things exist. Accordingly, God turns out to be non-existent by definition! (If only it were that easy to defend atheism.) Likewise, minds, thoughts, numbers, sets, propositions, and all other non-physical entities are dismissed as “merely imaginary” by sheer verbal fiat. (That would include, presumably, the mind of the person who contributed that definition of reality.)

The second sentence is unintelligible. (Among other sins, it grammatically confuses the word reality with reality itself.) The third sentence is even worse, if that can be believed. “Seems vague and academic”? What in the world?!

But then things take an even stranger turn. Here’s the next paragraph:

Philosophical questions about the nature of reality or existence or being are considered under the rubric of ontology, which is a major branch of metaphysics in the Western philosophical tradition. Ontological questions also feature in diverse branches of philosophy, including the philosophy of science, philosophy of religion, philosophy of mathematics, and philosophical logic. These include questions about whether only physical objects are real (i.e., Physicalism), whether reality is fundamentally immaterial (e.g., Idealism), whether hypothetical unobservable entities posited by scientific theories exist, whether God exists, whether numbers and other abstract objects exist, and whether possible worlds exist.

As it stands, this is quite respectable. But note that it contradicts the initial definition by observing that “whether only physical objects are real” is a live question among philosophers. If reality just is physical existence, the statement “Only physical objects are real” would be a trivial tautology rather than a matter of serious philosophical debate.

Now to be fair, the article has since been edited several times and the opening statements vastly improved. It now begins thus:

Reality is the sum or aggregate of all that is real or existent, as opposed to that which is merely imaginary. The term is also used to refer to the ontological status of things, indicating their existence.

I suppose someone might argue, “That’s why Wikipedia is so great! Blunders like these get fixed. Over time, the community improves and refines the articles.” Unfortunately, the history of the article tells a different story. It appears the question-begging physicalist definition was introduced on June 15 and not removed until September 14. Anyone who consulted the article in that three-month period would have been presented with a philosophical car wreck, right off the bat. Moreover, this wasn’t the first time a prejudicial definition had been introduced.

The point is not that some credulous person might have stumbled across the Wikipedia entry on ‘Reality’ and become a physicalist (although nothing would surprise me in a world where people ask Google how they should vote). The point is that Wikipedia isn’t a reliable source for definitions or explanations of disputed subjects. If it can’t be trusted to deliver you a respectable definition of a basic concept like reality, perhaps you should think twice about making it your go-to reference on more complex topics.

Incidentally, this isn’t the first time I’ve come across confused attempts to make physicalism true by definition. Years ago I got into an exchange with an atheist who insisted that X exists and X is material are synonymous. No amount of argument could dislodge this basic category confusion from his mind. (Try replacing X with Santa’s sleigh to see the problem.) Lawrence Krauss is another culprit. In an interview with fellow atheist Sam Harris, Krauss makes the astonishing claim that “‘something’ and ‘nothing’ are physical concepts.” (He wades even deeper into the mire by attempting to argue that ‘nothing’ is really something after all — a physical something, of course!)

Since it’s hard to know whether to laugh or to cry at these semantic antics, let’s choose to laugh, courtesy of a classic clip from Stephen Colbert: