I was talking with a young philosophy student the other day. She is studying epistemology in an intro class at VIU. I told her about an imagined pub discussion with construction workers and one philosophical skeptic – a discussion in which every claim made by one of the workers [CW] was challenged by the smart-ass philosopher [SAP].
• CW: There are three beer on the table. Now that’s for certain!
• SAP: Well you may believe that there are three beer on the table, but do you know it?
• CW: Of course. Look there they are. Can’t you count?
• SAP: Yes, I can count, but how do you know that they are real? Isn’t it possible that they are holographic images? Or, perhaps you are dreaming about beer??
• CW: Well, I guess I could be dreaming. This evening is starting to feel like a nightmare.
• SAP: There you go. You cannot be certain that you are having a veridical “three beer on the table” experience” can you?
• CW: Let’s ask others. (lots of people look and see three beer on the table) There you go – more evidence for my claim.
• SAP: But, if you could be mistaken, couldn’t everyone be mistaken?
• CW: Not bloody likely!
• SAP: Ok, but there is a chance that we are all dreaming, eh? Or, what if we are all just a bunch of brains kept alive by some Martians (remember those brains in Star Trek?) for their entertainment in their pub when the day’s work is over. Is that possible? And if so, can you really claim to know??
• CW: Let me generalize your position: you’re saying if a claim is dubitable then I cannot know it?
• SAP: Yes, that’s it.
• CW: Ok, got it. Let me put your argument in standard form. 1. If P is dubitable then I cannot know that P. 2. P is dubitable. 3. So, I cannot know that P. Right?
• SAP: That seems just right. Any claim (P) you make I can show to be dubitable.
• CW: (picking up one of the glasses of beer and drinking it) Ok, SAP. Now stick this claim in your argument. Let P = “if P is dubitable then I cannot know that P”.
• SAP:
• CW: Look, lads, the SAP is speechless.