the_recruit said:
I'm using "know" in the sense of "we know that the sun is a gaseous ball of hydrogen fusing into helium " or "we know cells contain DNA". Importantly - does not mean that it's impossible that we could be mistaken about these claims. It is not impossible that the sun is made of something different. This kind of knowledge is contingent on certain hypotheses being true.
A theory of knowledge has to answer some basic questions, most particularly in this case: what is the source of knowledge?
the_recruit said:
Not in the sense I mean. We can know what other people are experiencing. In fact we do so all the time. You wouldn't be able to get far in life if we weren't able to ever know what other people think or feel.
For example, I know that a man who puts his finger into a flame, then jerks back, makes a face, and cries ouch experienced pain...(snip)...We are able to know that he experienced pain because we have a theory about how mind works - that conscious experience supervenes on physical happenings in the body/brain.
OK, but a panpsychist has a theory as well--that consciousness is a fundamental property of all things. If, as you've said, knowledge is based on contingent hypotheses, this one fares no worse than a theory of mental/physical supervenience. And anyway, all this misses the point, which I might state another way: in order to support an anti-speciesist ethic, certain metaphysical assumptions have to be made. Someone who has grounds to reject those assumptions (or even someone who just rejects them) has no reason to be impressed by arguments against speciesism.
the_recruit said:
That a being with a sufficiently similar body/brain will have similar experiences to mine.
This is not entailed by mere mental/physical supervenience. You need an additional assumption that such supervenience is nomic...and I think there's a good bit of evidence that the relations between mental and physical are not very nomic. We know that type identity theory is probably false (to steal a point from Dan Dennet: if it were correct, and, say, someone believed that a frenchman was once assassinated in Trafalgar Square, then everyone would have to have some frenchman neurons, an assassination ganglion, a Trafalgar Square cortex. We don't. Ergo, type identity theory is false). Token identity theory could be correct, but of course token identity isn't nomic. Generally speaking, the papers I've read wherein researchers use fMRI data coupled with an algorithm to try to predict decisions subjects will make tend to show that at least decision making isn't nomic, since subjects have to undergo a calibration process. The calibration data which works for one subject doesn't work for another. Interestingly, from what I've read, the same subject tested again the next day has to be re-calibrated, as the previous day's calibration data doesn't work for that subject again the next day.
Anyway, all of this ignores an overarching point, which is that mental/physical supervenience is entirely compatible with panpsychism. A panpsychist may claim that necessarily, mental events supervene on all physical events.
the_recruit said:
Of course this tool we have for determining what others are feeling has limits. I have no idea what Nagel's bat is experiencing when it's echolocating, or a fish's lateral line, or migrating birds etc. Because I'm not sufficiently physically similar to them in these areas to know.
Then how do we know that animals experience suffering?
the_recruit said:
Panpsychism introduces an enormous number of conscious beings that are nothing like us....(snip)...Ethics suddenly becomes an epistemic nightmare
Not necessarily a nightmare. There may be nothing wrong with causing suffering.
the_recruit said:
First of all, this whole "principle of harm" is entirely your proposal. So you're beating up a straw man here. OP seems to be advocating some kind of utilitarianism.
Well, I've extracted it from what the OP says, but it seems to underwrite anti-speciesism. Why should we avoid harming animals, according to an anti-speciesist? The answer has to involve something like the principle of harm somewhere, since if there's nothing wrong with causing harm, there doesn't seem to be a reason to accept anti-speciesism. At least not with the arguments that have been presented so far.
the_recruit said:
Minimize suffering or something. Perhaps with certain caveats. Nothing that he's said implies that "doing harm is wrong" is to be taken as an absolute moral truth.
My fault for not stating things a little more clearly: the principle of harm I'm proposing entails merely that in most ordinary circumstances, causing harm is wrong. If that principle is false, again, there's no reason to accept speciesism. This is the reason I went straight to panpsychism--a panpsychist has a hard time accepting even a very minimal principle of harm.
