All of Sister_Y's Comments + Replies

Constant - I'm not sure I comprehend your distinction (could be lack of caffeine) but thanks for the recommendation.

poke - my friend likes to explain this to his undergrads by asking them how they would verify that a thermometer is accurate (check it against another thermometer, but how do you know that one is accurate . . . etc.) until they figure out that thermometers are only "accurate" according to custom or consensus. Then he asks them how they know their eyes work. And their memories.

Some of them cry.

Okay maybe not really. Anyway, aside fro... (read more)

Edit: Now I see Sister_Y addressed my point in the very next paragraph, so this entire comment is a reading comprehension fail more than anything. Necroing: Go to the beach, light a fire, boil some water. Put the thermometer in the boiled water - does it show 100 degrees Celsius? Still at sea level, put a cup of water in a fridge untill it starts freezing. Put the thermometer in the cup - does it show 0 degrees Celsius? If yes to both, you have a working thermometer. This way, you don't rely on the consensus of other thermometers. As for the custom of calling a working thermometer accurate - that's what it is for. Eyes and memory can be similarly tested. Of course, accepting the results of such tests requires acceptance of induction from the past. Maybe the realization you've faced "Last Thursdayism" for the first time at undergraduate level is something to cry about, but no one actually does. Lest I sound too smug, rest assured I am not convinced I would've done better before finding Less Wrong.

poke, interesting that you're talking about the middle ground between skepticism and the infallibility of sense data, which is the sort of "defeasible warrant" idea - we DO take our sense data as a starting point (or, as you note, we take a theory as our starting point - though where did the theory come from, ultimately, but somebody's taking his sense data seriously and then interpreting them?) - but if we find a conflict, either among our sense data or between ours and somebody else's, we reduce our trust in our sense data (we don't just toss them out). People are starting to apply this line of thinking not just to straight epistemology but to ethics (and even aesthetics!).