Jonathan asked:
Am I here?
Answer by Helier Robinson
Yes, of course. If you were not you could not ask the question.
Answer by Geoffrey Klempner
The first thing we need to establish is who is asking the question and also who is being asked.
It seems absurd to ask myself this question. If I ask a question, or do anything, then it necessarily follows that I exist. Descartes says something along those lines. And if I exist, I must be somewhere, mustn’t I? But then again, strictly according to Descartes’ mind-body dualism, although my body has spatial properties and is therefore located in space, my mind has no spatial properties and therefore cannot ‘be’ anywhere in particular. (Nor would it be correct to say that it is ‘everywhere’, in the sense that space or gravity is everywhere.) For an ‘I’ which is metaphysically distinct from body, there is no ‘here’. What there is, is only the mysterious physical/ metaphysical link that enables mind-body interaction, which for obscure reasons Descartes believed to occur in the pineal gland.
For any variety of physicalist, on the other hand, the answer is necessarily, Yes. It is always true that I am here. To be the kind of entity that is capable of being ‘I’ is necessarily to be located in space. But then again, why should it be necessary that I am here and not also there? Suppose I have a perfect double on twin earth. As I type these words, so does my twin earth double. Are we two or one? Would it be so absurd to say that, rather than it being the case that there are two versions of GK, the entity referred to (that I refer to myself as) ‘GK’ exists in two places simultaneously? In that scenario, ‘I am here’ is false, when understood in the sense of, ‘I am here but not there.’
But you are asking this question of me. How do I know that you exist? Maybe the words were caused by a cosmic accident, a highly improbable but nevertheless logically conceivable sequence of web server errors that caused the Ask a Philosopher form to be submitted and delivered to the Ask a Philosopher mailbox with just that sequence of characters.
Or more likely, between the time when you submitted the form, and I replied, you passed away. You are no longer here. That’s something I could find out, but right now I don’t know the answer to that question.
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