Future Perfect

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While browsing around the library one day, I notice an old dusty tome, quite large, entitled ‘Alvin I. Goldman.’ I take it from the shelf and start reading. In great detail, it describes my life as a little boy. It always gibes with my memory and sometimes even revives my memory of forgotten events. I realize that this purports to be a book of my life and I resolve to test it. Turning to the section with today’s date on it, I find the following entry for 2:36 p.m. ‘He discovers me on the shelf. He takes me down and starts reading me …’ I look at the clock and see that it is 3:03. It is quite plausible, I say to myself, that I found the book half an hour ago. I turn now to the entry for 3:03. It reads: ‘He is reading me. He is reading me. He is reading me.’ I continue looking at the book in this place, meanwhile thinking how remarkable the book is. The entry reads: ‘He continues to look at me, meanwhile thinking how remarkable I am.’

I decide to defeat the book by looking at a future entry. I turn to an entry 18 minutes hence. It says: ‘He is reading this sentence.’ Aha, I say to myself, all I need do is refrain from reading that sentence 18 minutes from now. I check the clock. To ensure that I won’t read that sentence, I close the book. My mind wanders; the book has revived a buried memory and I reminisce about it. I decide to reread the book and relive the experience. That’s safe, I tell myself, because it is an earlier part of the book. I read that passage and become lost in reverie and rekindled emotion. Time passes. Suddenly I start. Oh yes, I intended to refute the book. But what was the time of the listed action?, I ask myself. It was 3:19, wasn’t it? But it’s 3:21 now, which means I have already refuted the book. Let me check and make sure. I inspect the book at the entry for 3:17. Hmm, that seems to be the wrong place, for there it says I’m in a reverie. I skip a couple pages and suddenly my eyes alight on the sentence: ‘He is reading this sentence.’ But it’s an entry for 3:21, I notice! So I made a mistake. The action I had intended to refute was to occur at 3:21, not 3:19. I look at the clock, and it is still 3:21. I have not refuted the book after all.

— Alvin I. Goldman, “Actions, Predictions, and Books of Life,” American Philosophical Quarterly, 1968

Goldman’s point is not that determism is true, but that it could be. It’s possible to imagine a determined universe, even one in which your own actions are accurately predicted, that unfolds in a way that makes it appear quite similar to our own. “The fact that this imagined world is determined and contains predictions of acts, and yet resembles the real world very closely, suggests to me that the real world may also be determined,” Goldman writes. Might it?