Haven't read the comments or the entire post, but got to the square circles part.
Out side of the context in which the argument is being made, square circles do exist. A shape with 250 sides can be considered a circle, just like a shape with 4 sides can be said to be a circle. Since a circle is defined as something like every point on the circle is equidistant from its center, it can be said that no circle even exists because you can never have a perfect circle, and if the shape doesn't fit the criteria of the definition, it follows that it must be something else.
But a square is not simply a shape with four sides. A square is defined as “a rectangle having all four sides of equal length” (source: Dictionary.com), while a rectangle is defined as “a parallelogram having four right angles” (source: Dictionary.com). The distinguishing feature of a square, then, is that it is an enclosed shape having four sides of equal length that are both straight (not curved), joined together by right (90-degree) angles, and “having both pairs of opposite sides parallel to each other” (source: Dictionary.com).
The commenter himself offers that “a circle is defined as something like every point on the circle is equidistant from its center.” Compare this with the definition I found at Dictionary.com: “a closed plane curve consisting of all points at a given distance from a point within it called the center.” So a distinguishing feature of a circle is its curved circumference. And while the circumference of a circle is a continuous, unbroken curve, a square has four straight sides of equal length and four right angles. Given these definitions, I do not see how one could argue that square circles could exist. Even if one wants to say that a figure with 250 sides is a circle, it seems that, given the distinguishing feature of a circle being its unbroken curved circumference, each of those 250 sides are curved in such a way that when they are assembled together in a particular configuration, they form a continuous curve in which every point is a given distance from its center. But that would not be a square.
The commenter then suggests that “it can be said that no circle even exists because you can never have a perfect circle,” which seems to blow his entire point out of the water. If it is accepted that there can be no circles to begin with, then on what basis could one hold that a square circle exists? Blank out.
The point I was trying to make in the context of my original blog entry by raising the specter of “square circles” should be clear from what I state there. There is an internal tension between (a) the apologetic premise that one would need to scour the entire universe to ensure that there is no evidence for the theist’s god, and (b) the recognition that there are no such things as “square circles.” Apologists who acknowledge the fact that there is no such thing as a square circle on the basis that such a notion is conceptually incoherent, are not demanding that we scour the universe to ensure that there is no evidence of any square circles that might be hiding someplace within it. It is accepted by such apologists that the notion of square circles can be safely rejected on the basis that such a notion is conceptually incoherent. Thus, if the notion of “God” is likewise shown to be incoherent, we should accept that the notion of “God” can be safely rejected for essentially the same reason.
Besides, Christians claim that the universe was created by their god, which would mean that their god is not a part of the universe in the first place. So even if one did scour the universe for evidence of the Christian god and found none, the Christian could simply say that we’re looking in the wrong place to begin with. So the whole apologetic angle on the matter is shown to be a complete ruse from the outset. Meanwhile, the apologist is hoping that we do not discover the fact that his god is nothing more than something he’s been imagining all along.
by Dawson Bethrick