The Nature of Phenomenal Qualities

Project: Research

Project Details


This project will explore issues connected with the exact nature of the phenomenal aspects of experience. In perceptual and related experiences subjects are aware of a range of phenomenal qualities: these are the colours, sounds, and so on, which are immediately present in conscious experience. There is currently broad-ranging debate about the reality and cognitive role of phenomenal qualities. There is no settled view about their status either as subjective - belonging to inner mental items of some kind - or as objective, dependent in some way upon the properties of the surrounding objects perceived. Nor is there agreement about the ultimate ontological status of phenomenal qualities, and how they are related to the entities postulated in our best current scientific explanations about the underlying structure of physical things.

The research will seek to answer the following questions:
(1) In what sense can we say that phenomenal qualities exist? What is the relation of phenomenal qualities to cognitive processes? Do they form a distinct component in consciousness, or do they, in some respects, parallel conceptual states as distinctive perceptual ways of representing facts about the world?
(2) How are phenomenal qualities related to the mind? Where are phenomenal qualities located - are they subjective states of the experiencing subject? Or should phenomenal qualities, at least when they occur in normal perception, be understood as in some manner dependent on the objective properties of the external objects perceived?
(3) What is the ultimate ontological nature of phenomenal qualities? How can we reconcile our current scientific theories about the real underlying physical nature of persons and objects with the existence of conscious experience and with the phenomenology of perception? Should we embrace a radical revision or extension of fundamental physics, as some theorists suggest?

Layman's description

The Project’s aim has been to investigate the nature of phenomenal qualities – the distinguishing properties of conscious experiences, those properties that make each experience what it is as distinct from experiences of other kinds. The itchiness of an itch and the blueness of a perceived sky are examples of phenomenal qualities. What makes seeing red different from seeing blue is, at a minimum, the different qualities involved.

Central questions concern (i) the location, and (ii) the nature of phenomenal qualities. The location question is whether we should take phenomenal qualities to belong to the subject’s mind, or whether we should take them, at least in normal circumstances, to belong to objects perceived. When one sees the blue sky, is the blueness a feature of oneself, or of the sky? The difficulty is that while we normally understand phenomenal qualities to belong to things we perceive, we experience such qualities also in hallucinations and dreams, where they cannot belong to anything mind-external. The nature question is whether phenomenal qualities can be understood as physical properties, which comes to the question of whether they can be scientifically analysed. If phenomenal qualities belong to mental states, the nature question becomes whether e.g. visual blueness can be understood in terms of neural going-on. If blueness belongs to the sky, the nature question is whether visual blueness can be understood in terms of such things as light wavelength reflectance. The difficulty is that although we have ample reason for taking phenomenal qualities to be physical—notably, because they have physical effects—no physical analysis gets anywhere near capturing the colourfulness of a colour, or the feel of an itch.

Key findings

Our findings on these questions are as follows:

We consider that phenomena like hallucinations and dreams constitute strong support for a construal of phenomenal qualities as belonging, in a sense to be settled, to the subject’s mind. Papers were invited defending the external view of phenomenal qualities, and criticising such ‘arguments from hallucination’. We accordingly accept there may not be a strict argument for phenomenal quality internalism, but do consider the hypothesis the best explanation of the evidence. The alternative requires phenomenal qualities to be sometimes mind-generated (otherwise illusory, an option we wholly reject) and sometimes external, without us being able to tell the difference. It is difficult to justify this disjunctive treatment of such qualities, and it has problems in providing a clear positive account of the relation between our consciousness and external located qualities. We are therefore unpersuaded by criticisms of the internal view.

To retain the causal efficacy of phenomenal qualities, thus accepting their broad physicality, whilst respecting the datum that they are not analysable by current physical concepts, we favour the conclusion that they may need to be fitted into the physical world in a more subtle way. We (tentatively) advocate a Russellian view, on which while physics describes the doings and relationships of fundamental physical particles, it leaves out any characterisation of their intrinsic nature. We find it a plausible suggestion that this nature is qualitative, i.e. of the same sort as the phenomenal qualities we experience. This would explain how qualitative consciousness is generated from purely physical ingredients (our bodies and brains), whilst giving phenomenal qualities a firm causal role within the physical world.
Effective start/end date1/02/0930/09/13


  • UKRI - Arts and Humanities Research Council (AHRC): £296,588.00


Explore the research topics touched on by this project. These labels are generated based on the underlying awards/grants. Together they form a unique fingerprint.