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Question Someone asked [http://www.askphilosophers.org/question/1411], "How do we know our right hand from our left hand when there is literally nothing that can be said about one which cannot be said about the other"? Mark Lange posed this question in turn, "Suppose there were a universe that was utterly empty throughout its history except for a hand (unattached to any body) floating in it. (Pretty gruesome, but let's not think too hard about that!) Would that hand be a right hand or a left hand? Now we cannot appeal to the hand's relations to other things to give it its handedness, since there are no other things." The thumb is on different sides of each hand. Put the palm down and you can tell which hand it is by looking to see if the thumb is on the inside or outside. What am I missing? Gloves come in left and right, you know? You could even tell this in a void.

Accepted:
April 22, 2009

Comments

When you imagine a space that is empty of everything except one hand, you are still imagining the appearance of that hand from a particular point of view (or, perhaps, from several different points of view). That point of view is what tells you it is a right hand versus a left hand, for it is from that point of view that the thumb extends to the left of the the palm rather than to the right.

Some philosophers (e.g. Berkeley) have claimed that imagining anything requires you to imagine the existence of a viewing subject. There is a difference, however, between imagining how a hand looks from a particular point of view and imagining that someone is occupying that point of view. (This distinction is nicely clarified in an important article by Bernard Williams, entitled "Imagination and the Self" .) You can imagine what a particular hand looks like from a particular point of view without imagining that there is anyone occupying that point of view.

If you agree with Berkeley that imagining something in space requires you also to imagine an observer of that thing,then it is not possible to imagine a space that contains a hand and nothing else. At best, you could conceive of a hand in an otherwise empty space -- supposing or stipulating the existence of such a thing without actually visualizing it. To further stipulate that it is a right rather than a left hand would only be meaningful, though, insofar as one supposed that there is a possible point of view onth hand -- a point of view that could be taken if there were also a subject in that space.