Question There are many attributes that are commonly attributed to God, or at least some versions of the Christian God, one of which is omniscience. I have my doubts that omniscience is a possible trait for any being to have because it seems to me to be a paradoxical trait. If God (or any being) knows everything that can be an object of knowledge can s/he know what it is like to not know everything that can be an object of knowledge? I say everything that can be an object of knowledge because there are obviously things that are unknowable like a round square or a married bachelor. However, I don't think that a being could know everything that was knowable and simultaneously know the experience of not knowing everything that it knowable (knowing the experience of not knowing everything that is knowable is something that is knowable because as humans that is how our experience is).

Accepted:
July 29, 2010

Comments

Thank you for your question. This is a good one that I had not heard before. If I understand you correctly, you are concerned that the notion of omniscience is not coherent. The reason is that omniscience means knowing everything. However, if a being knows everything, then it knows what it is like to be ignorant of something. However, to do that, such a being would have to have the experience of being ignorant of something, and that in turn requires that it is, or at least has been, ignorant of something--but that contradicts the definition of ignorance! This is, I take it, an epistemological analogue of the Paradox of the Stone, namely the question whether an omnipotent being could do something it is impossible to do (like make an unliftable stone).

Someone who wants to defend the coherence of the notion of omniscience might, however, not be convinced that you've raised a compelling objection. The reason is that your objection assumes that to know what ignorance is like, you have to experience it firsthand. However, this assumption is doubtful. It may well be true that to know what the color red looks like, or how the smell of sulfur smells, you have to experience these things firsthand. However, ignorance is not an experiential notion like vision or smell. Rather, it is more like not being tall enough to reach something. Even if I am tall, and (to be picturesque) have always been, and so have never had an experience of not being tall enough to reach door handles, I know what that would be like: I can simply imagine reaching for the handle and not being able to grab it. So too, our omniscient being can imagine what it would be like to be ignorant of something: it would only need to be able to imagine attempting to answer a question and not being able to do so.

So I suspect that a defender of the coherence of omniscience might reply by saying that it's not clear that you've shown the concept to be incoherent. On the other hand, you might wonder whether an omniscient being can know what free agents are going to do before they act. (Theologians and Philosophers have worried about this one.) And you might wonder whether a disembodied being, such as God or an angel, can have knowledge of emotions and experiences, and not just knowledge of facts. For a inquiry into the latter question, you may enjoy Wim Wenders' movie _Wings of Desire_, in which an angel considers giving up eternal life in order to gain one or both of these sorts of knowledge.

Mitch Green

Just a minor addition to Mitch Green's astute observations: Some defenders of the coherence of omniscience (Richard Swinburne, for example), hold that omniscience does not include the knowledge of future free acts. Swinburne and R.M. Adams and others do so on the grounds that there is no truth or falsehood now about what a future free agent will do. Aristotle held this as well (or at least most commentators think so!). If this viewpoint is correct, "omniscience" would mean something like all that it is possible to know or all that can be known. If future free action is not knowable in principle then any being, even an omniscient being, would not know something and thus would know what it is like to be ignorant. For an excellent book on omniscience and other divine attributes, check out Richard Swinburne's The Coherence of Theism.

Professor Green rightly notes that some philosophers have worried about the limits of knowledge that might be in play if a being is incorporeal. And I must agree that Wings of Desire is a most excellent film. I would only add that problems arise for theism only depending upon your view of emotions, sensations, and perception. If you believe that these are only and exclusively physical processes and states (that is, if you believe it is a necessary truth that such processes cannot be nonphysical or be entertained by an incorporeal being ), then God (if God exists) does not have such processes and states, but significant numbers of philosophers believe that either such processes are not themselve exhuastively physical with us or other animals (John Foster, Howard Robinson) or they maintain that these processes in us are physical but only contingently so. Thus, Peter VanInwagen accepts a materialist view of humans and our cognitive powers, but he is not a materialist when it comes to God and divine cognitive power.