Could you ever hope to observe – visually or otherwise – the conscious experiences of others? Before venturing an answer to this question, it is important to understand what is being asked and why answers have proved so elusive.
Philosophers, psychologists, and neuroscientists vigorously debate solutions to what David Chalmers calls the Hard Problem of consciousness: how are conscious experiences to be reconciled with our emerging understanding of the material world? Many who accept that consciousness has a neurological ‘substrate’ reject the reduction of the mental to the physical because this seems effectively to eliminate the mental. On the one hand, we seem intimately familiar with qualities of our conscious experiences, experiences that mediate our awareness of the physical universe. On the other hand, the qualitative nature of these experiences seem altogether to elude the physical sciences. From the scientific perspective, conscious phenomena seem alien and utterly mysterious.
We face a dilemma. Conscious qualities appear to reside alongside the physical realm, so we seem bound to accept to some brand of unsavory dualism. Including conscious qualities amongst states and events of the kind studied by the physical sciences, however, obliges us to ignore everything that makes them so distinctive.
The acuteness of the Hard Problem is thought to result from two widely advertised features of conscious experiences.
First, conscious experiences differ qualitatively from physical states and processes. (To simplify the discussion, I shall ignore differences among observers – color blindness, for instance – and variations in conditions under which objects are observed. These are irrelevant to what is at issue here.) Even if you allow that your experience of a red tomato is intimately related to goings on in your brain – conscious states are thought at a minimum to be correlated with neurological processes – the qualities of this experience appear to be nothing like qualities encountered by scientists who spend their careers studying brains. There is ‘something it is like’ to have a visual experience of a ripe tomato, for instance, and this is nothing at all like what you come across when you examine, by whatever means, the brain of someone undergoing the experience.
The problem of conscious qualities – the ‘qualia problem’ – is taken to be particularly vexing because it is difficult to imagine any physical discovery revealing anything remotely like qualities of familiar conscious experiences. So even if we post-Cartesians are confident that brains are the source of consciousness, an account of how this is supposed to work appears hopelessly out of reach.
Second, conscious experiences are ‘subjective’. In addition to there being ‘something it is like’ to undergo a particular conscious experience, every conscious experience is ‘like something’ only to whomever or whatever undergoes it. Your relation to the qualitative character of your own experiences is privileged, at least in the sense that there is a fundamental asymmetry between your ‘access’ to your own experiences and anyone else’s. Your access is ‘direct’, unmediated; the access of others is indirect and inferential.
These two aspects of consciousness effectively bifurcate the universe along two axes. On the one hand, conscious qualities differ from physical properties. On the other hand, conscious qualities, unlike physical phenomena, can only be apprehended from the ‘inside’, from a subjective ‘first-person perspective’. Sciences that provide our best portraits of the physical universe take up an objective perspective that is notably ill-equipped to tackle an essentially subjective domain. Science encounters conscious experience only from the ‘outside’, the distinctive subjective ‘inner’ character of experience remaining, like the horizon, forever out of reach.
"Science encounters conscious experience from the 'outside', the subjective 'inner' character of experience remaining, like the horizon, forever out of reach."
Most of the discussion of consciousness has focused on what is thought to be the special qualitative character of conscious experiences. My own view is that the water has been muddied by a tendency to conflate qualities of what is experienced with qualities of experiences. Your visual experience of a ripe tomato is an experience of something red and spherical, but it is the tomato, not your experience, that is red and spherical.
I will not pause to elaborate this point here. Rather I shall focus on the second aspect of consciousness mentioned earlier: its ‘subjective’ nature. The thought is that you are privy to your own experiences in a way no one else could be. Experiences are private, unobservable, in principle, from the ‘outside’. In contrast, goings-on inside your body, including goings-on in your brain, are observable by anyone with the right equipment. It is all well and good to suppose your experience of a ripe tomato is correlated with an occurrence in your nervous system: a neuroscientist might observe and measure the neural correlate of your experience. But it makes no sense to imagine the neuroscientist’s observing your experience.
Really? Consider what it would be for a scientist to observe your experience. If you are careful to distinguish qualities of what is experienced – the redness of a tomato, for instance – from qualities of the experience, you can see that it would be a mistake to expect a scientist observing your experience of a red tomato to observe something red and tomato-shaped. This leaves open the possibility that your experiencing the tomato is an occurrence in your brain that could in fact be observed by others.
Were that so, it would seem to undermine the powerful sense that experiences are distinctively private affairs: subjectivity sacrificed on the altar of objectivity!
Maybe not. Consider, first, the difference between something being in a given state and observations of something being in that state, and pretend for a moment that your undergoing a conscious experience is for your brain to be in a particular state. Now, imagine a neuroscientist observing your brain being in that state. The neuroscientist’s observing of your brain state is itself a matter of the neuroscientist being in a distinct experiential state. Why think that the neuroscientist’s experience of your experience of a red tomato would resemble your experience of a red tomato or, more generally, that a neuroscientist’s observation of any conscious state would yield an awareness of ‘what it is like’ to be in that state? What is misleadingly described as your awareness of your own experiences is not your inward observation of those experiences, but simply having or undergoing those experiences. Assuming it makes sense to identify experiences with neurological states or processes, having and observing an experience are two very different things.
What of the elusive ‘what-it’s-like-ness’ of experiences? Knowing what it is like to experience red apparently requires having undergone a ‘red experience’, that is, having visually encountered something red. The point is a perfectly general epistemological point having nothing in particular to do with experiential qualities. Knowing what an echidna looks like requires having encountered an echidna, or a picture of an echidna, or a creature you know to be echidna-like.
None of this is especially controversial. If visually experiencing a tomato is a matter of being in a particular perceptual state, a scientist experiencing that state is a matter of the scientist being in a distinct perceptual state. These states – yours and the scientist’s – need not be similar, qualitatively or otherwise. And if knowing what it is like to be in a particular state is a matter of being – or having been – in that state, knowing what it is like to experience a tomato visually differs from knowing what it is like to experience a visual experience of a tomato. You could know either without knowing the other.
The subjectivity of experiences stems, not from their in-principle unobservability from the ‘outside’, but from the relatively humdrum distinction between something being in a particular state and someone observing that state. The distinction applies to mental and nonmental phenomena alike. A quantity of water being in a liquid state is one thing, you observing the water being in that state something else altogether.
Let’s not make the Hard Problem harder than it needs to be.