Hi, My roommate claims that it is impossible for an omnipotent being to exist. His logic is that if a being can create a rock so big it cannot lift it, then that being is not omnipotent because its lifting power is not infinite. But also, if it cannot create the rock so big it cannot lift, then it's creation power is not infinite. And because of this paradox, an omnipotent being cannot possibly exist. My boss was a philosophy major in school. He claims that this explanation is completely wrong. However, I do not understand his explanation as he said it very quickly and with many names of old philosophers and theorems and such that I cannot remember. So who is right? Regardless of whether or not an omnipotent being does exist or not, can one exist? Thanks.

Richard Heck
October 6, 2005
This is a version of an old problem, one discussed endlessly by theologians. In its simplest form, it goes like this: Can God make a rock both big and small? Obviously not. So God isn't omnipotent.

If you think that's a cheat, I'm with you. It's not possible for there to be a rock that is both big and small, so it's not limit on God's power that God can't make a rock like that. We have to be more careful in how we understand omnipotence. It's a delicate question how we should understand it, but a first stab might be: A being is omnipotent if, whenever it is possible that p, that being can bring about that p.

The puzzle your roommate presents you is of this same form. If Fred is omnipotent, then it simply isn't possible for a rock to be so big that Fred can't lift it. So it's no limit on Fred's power that he can't create a rock that big. Of course, maybe Fred isn't omnipotent, and maybe it's not even possible for there to be a being that is omnipotent. But the argument your roommate offered does not prove either conclusion.

Steven Gerrard
October 7, 2005
There are two traditional theistic answers to this question (well, three, if you count: “you’re a heretic, where are my matches”). The first, favored by Descartes, is that God’s powers are truly unlimited, and He is not even limited by the laws of logic. It is not for us finite and imperfect beings to understand or criticize an infinite and perfect being’s ways. The second, favored by Thomas Aquinas, is like Richard Heck’s answer above. To be omnipotent means to be able to do anything; a contradiction is not a thing: therefore not being able to create a stone so heavy one can’t lift it is not a thing that can’t be done. To some readers this puzzle might seem silly, but it actually mirrors some contemporary controversies about the nature of logic. Are logical inferences hardwired into our brains? That is similar to Descartes’ answer. Are logical inferences constitutive of rationality? That is similar to Aquinas’ answer.

Mitch Green
October 21, 2005
I'd like to add one further point to the two made so far. Many contemporary philosophers infer from the so-called Paradox of the Stone that omnipotence is not a matter of being able to do anything, but only a matter of being able to do anything it is possible to do. That observation suggests another possible insight. Consider the Problem of Evil. If God exists, then it might seem puzzling that God should permit the extent and kinds of evil that we can find. Now there are many things to say about this, but one pertinent to God's omnipotence is this: Certain moral virtues seem to require some evil, and in such a way that even God can't have one without the other. Even God, it might be remarked, can't make a world in which there is, for instance, forgiveness in the absence of any wrongdoing. (I can't forgive you unless you've wronged me in some way.) This is not to say that all virtues require evil, but just that some seem to, even if you're God. As it happens, contemporary philosophical theologians like Alvin Plantinga have made much of how God's powers might be surprisingly limited, while remaining omnipotent!

Question 26

In most of The Arts, 'After Name' means 'in the style of Name'. One commonly sees the phrase used in the Performing Arts: in classical dance, for example. In Fine Art auctions, however, a little more care must be taken. Auction houses may use slightly different definitions in their nomenclature, some use more terms (so the terms can get quite specific) some use fewer terms (so those terms have more of a range of meaning) but to be safe, you should err on the side of caution. If you see the phrase 'After Name' in an art auction catalog, assume that the work you're looking at is a copy of Name's work and it could have been made a hundred years ago, or sometime last week. It doesn't mean 'made by his team' because there are other terms for that, such as 'Studio of Name' or '(The) Workshop of Name', 'School of Name' or 'Circle of Name' (these have nuances of meaning, and of these, 'Circle of' is the least likely to be by one of Name's workers or pupils, but it does imply that it was somebody who was a contemporary of Name and admired him/her). Then you've also got 'Style of', 'Follower of' and 'Manner of', until finally we arrive at 'After...' It does not mean 'it's a fake' because the intent is not to defraud; Name didn't create it and this is known by everyone who is familiar with Name's original work (on which this is based) and it is plainly stated. Okay, maybe it's not so plain for newbies, but you'll catch on to the lingo of the auction world really fast, especially if you go often. It does not mean 'well, we think he made it' because there are other terms for that. As to...'he just signed it' well, no...artists don't just sign work that isn't theirs, though they may sign if they did part of the work and someone like a pupil filled in other bits (backgrounds, e.g.). There might be an imprinted or engraved signature or maker's mark on items in the decorative arts where the artist created the design from moulds or plates and then their facsimile signature is placed on the finished pieces by stamping, etching or what have you, but I don't think that's what you're talking about here.