I just posted Joshua Spencer’s intro level talk Time Travel and Freewill. Check it out. Spencer kicked off our 2009-2010 Young Philosophers Lecture Series.
I’ll post Spencer’s research talk “A New Counterexample to Principles of Alternative Possibilities” by sometime tomorrow.
Also note that we have four excellent speakers delivering talks as part of the series next semester. Here’s the line-up.
Aside: We purchased a Flip Ultra HD to record the video for Joshua’s two talks. We’ve had technical difficulties with other recording options with a couple of our other talks. The Flip is (a) awesome and (b) by-passes several things that were giving us some technical difficulties. From now on, you can expect to see young philosopher videos posted within a week or so after the original presentations.
Entertaining lecture–fun.
Spencer says the guy would not exist if he kills his grandfather, or does not save his grandfather, and so would not be able to go back in time, and so, since he did go back in time, it must be eclear that he did not kill his grandfather. The whole argument depends on what you allow as to time and alternative action.
I could that say that going back in time to before your birth is impossible since no one can exist before their birth at any time. If he tried to go back, he would simply disappear upon reaching past his birthdate. So the whole argument is moot in that case.
I could posit that time and fate is such that one may be born of several different people potentially–so that if one should die, the grandfather in question for instance, one will descend from another person of that time.
Spencer should remove substantially the ambiguity in the terms and circumstances as it relates to his argument such that he can simply say–“given this I am right”. If he leaves me free to create, for instance, my own idea of what alternative means and when an alternative action is possible or not, I surely can come up with an idea that weakens his argument. One may always define and limit terms and circumstances in the argument in order to secure the conclusion–that is what philosophers do best, it seems to me. Better to do so and just be up front with such premises.
Also, He hasn’t mentioned determinism versus free will but this is at the center of the issue.
Hi Wallace,
Thanks for the comment, and I’m glad you enjoyed the lecture. Some of the things you mention came up in question and answer, but we don’t post that portion of the talk.