In this old thread of mine:
Audio-visual perception - Factual Questions - Straight Dope Message Board
I posted the question of 'do we all perceive the same way".
It was explained to me this idea is in fact a philosophical concept known as Qualia…going pack as far as John Locke.
Apparently, qualia can now be scientifically tested.
Scientists Measure Qualia for First Time – It was thought to be impossible
Does this mean this field of study is no longer philosophy, but science?
Not if you read the comments, which overwhelmingly say that the studies did not prove any such thing.
3:00 NO, that is incorrect conclusion to draw from the experiment. The experiment didn’t measure qualia. It measured brain activity. There is every reason to ASSUME that similar brain patterns are a consciousness experiencing the same/similar qualia. There is no PROOF that the similar brain patterns aren’t mapped to DIFFERENT/UNIQUE qualia.
Hard disagree here. Philosophers have never tried to claim that physiologically the experience of red is different brain to brain. In fact, everyone assumes the processing of red would look the same physiologically. The hard problem of conciousness is that we don’t know what red feels like or looks like for each different concious subject that experiences it. We all process red in the same way, yet it evokes different emotions/feelings/sensations in all of us. They are no closer to answering the question of “why does it feel like something to see red”. They have simply said “look! This is your brain when you see red!” This is not qualia in any sense of the word.
Huh.
Could…any…such scanning/mapping technology, even theoretically, be considered “evidence” of qualia measurement?
They did not measure qualia. Video title is misleading crap.
This thread is probably of relevance:
I saw that video. It’s not measuring qualia. It’s measuring brain activity in response to sensation. The fact that there are correlations between different human brains with regards to similar stimulus gives no information about what each human brain is actually perceiving. Imagine a hybrid AI made of silicon and biological matter. Would an FMRI scan of the activity of that system give any idea if it experienced qualia or the nature of the qualia if it did?
I’m going to say no. Because measuring the state of a system isn’t the same as knowing what that system perceives. That might actually be fundamentally unknowable.
Though we may not yet be able to measure qualia differences in humans, I think we can point to the parsimonious nature of evolution to make an educated guess that there are no significant differences. To wire my brain so 650-nanometer light feels “red” while yours secretly feels “green” would demand extra developmental rules, extra fail-safes, and a lifetime of calibration. Evolution hates that kind of overhead. Ockham’s razor says, same hardware, same survival pressures, same subjective experience. Evolutionary parsimony makes significant qualia differences highly improbable, but not strictly ruled out.
If “qualia” even exist at all, then matching brain patterns implies matching qualia, because the mind, and all that goes with it, is an emergent property of the brain.
I’m not an expert on this, but haven’t we been using neural stimulation and recreational drugs to affect qualia for a long time?
The subjective experience of music changes on recreational drugs that mimic neurotransmitters. The subjective experience of pain changes on opiates or THC.
Recreational drugs like candyflipping (LSD + MDMA) will send you to subjective heaven, and drugs like salvia will send you to subjective hell. This is fairly consistent too in the sense that MDMA tends to produce similar subjective experiences among people, and those subjective experiences are different than the subjective experiences you have under things like ethanol or salvia.
Neural stimulation can cause people to see colors or smell odors that aren’t present.
I just want to push back against that random youtube comment.
Part of the hard problem of consciousness is that we can’t know other entities’ first-person experiences, so I can’t know that you and I see red the same.
But the problem remains even if we could somehow know we all see red the same*. We don’t know how brains make these experiences; that’s the central problem. And there is also the (related) description problem; even if we knew all hawks see UV the same, does that help with imagining what UV looks like?
* Actually red is a poor choice for these examples, because humans have different genes for the L-opsin pigment, responsible for detecting red light. It probably makes little to no difference in how we see red (and claims of tetrachromat humans remain somewhat tentative, and certainly nothing like a species with 4 pigments that hardly overlap in sensitivity range), but it’s the end of the spectrum that is less likely the same for all humans.
But now, thanks to work like this, we are starting to learn how brains make these experiences.
First tiny steps, perhaps, but by no means proof we experience stimuli in the same way.
The fact that individuals vary so much in many various ways suggests that our experiences are somewhat dissimilar.
Exactly this. Assuming “qualia” exist in the first place, if we understood them well enough we’d be able to identify them with the right sort of scanning device because we’d know what to look for. The issue isn’t that the mind is some magic thing scientific instruments can’t analyze; the issue is that we don’t understand the details of how the brain works well enough to know what the heck we are looking at most of the time.
Well that, and the practical difficulty of getting a close enough look at a brain in operation without cutting it into pieces and making it stop operating.
I beg to differ, somewhat. Salvia Divinorum can turn “bad” but all my experience with it has been good. DMT has been mixed, good and bad, but always interesting. I have had a terrible bad trip on MDMA. Never on LSD, though on some huge doses things got sketchy.
Who has not had what we refer in South Africa the experience of “mal dronk”… the sad, crying, feeling sorry stage shortly before passing out after excess alcohol use? But alcohol is still in widespread use.
I’m of the opinion that the “qualia” are too ill-determined for this thread to be really meaningful, and that is mirrored in real life.
Yeah, the word “starting”, in my post there, was doing a lot of heavy lifting. We’re very far from done.