Bhaskar’s own position is largely captured in a seven-part credo that begins chapter 8. First, “humanity is not the centre of the cosmos”. This means, roughly, that the “truth” about a subject does not necessarily consist of what human methods of investigation or human evidence disclose. In the same vein, conclusions about how things are experienced do not necessarily determine the nature of those things. Secondly, “there are non-actual realities”: reality contains possibilities and necessities in addition to actualities. Thirdly, “non-beings exist”: what is absent or unacknowledged, for example, the past, the presupposed, or the suppressed, can exist and be causally efficacious in either an impersonal process or a personal activity. Fourthly, “entities permeate one another”: things and processes may be interrelated in such a way that one is a necessary condition for the existence of the other. Totalities and their parts may be mutually involved in a deep metaphysical sense.

His fifth axiom, he says that “intentional causality occurs”: there is such a thing as agency. The sixth asserts that “values can be derived from facts”: a knowledge of natural necessities, power relations and so on, can show one that one ought (including morally ought) to act in certain ways. And, finally, “the good society is implicit in elemental desire”: there is an intelligible but complicated transformation of unreflective, possibly selfish, human desire into a demand for a democratic, ecologically conscious form of politics.

These seven points convey in a simplified form Bhaskar’s positive doctrine. They also illustrate his use of concepts such as absence and totality, which are also brought into his classification and “solution” of a wide range of philosophical problems. Among many others, Bhaskar discusses the problem of induction, a range of “problems of agency”, the relation of the natural to the social sciences, the problem of whether evaluations can be deduced from facts, as well as a host of difficulties internal to Kant’s critical philosophy, to Hegel’s reaction against Kant, and to Marx’s reactions against Hegel.

Many of his “solutions” to the problems he outlines are perfunctory at best and dependent on a baffling and largely idiosyncratic battery of technical terms and distinctions. There are polemical tours through the ancient, early modern and post Humean traditions on both sides of the Channel, and an appendix on “Explaining Philosophies”.

Plato Etc is the second of four volumes, the successor to Dialectic. Bhaskar claims in the preface that these two books together attempt no less a task than that “of reversing 2500 years of philosophical thought, in which negativity (absence and change), ontology, structure, diversity and agency come to the fore”. This is a staggeringly pretentious note on which to introduce a book, and it quite takes away the effect of his engagingly expressed dissatisfaction with recent philosophy.

Much of what he goes on to say is extremely obscure, but every so often one comes across a clear and highly inventive piece of observation or argument that keeps one on the author’s side. There were many scattered bits of the fourth chapter (on causality and emergence) that reawakened my sympathy for the book, but in between it was hard going. The chapter on dialectic contains many longueurs, and there are passages in the chapter on reference, truth and meaning that are fit only for Pseuds Corner. An example: “Here we need to be ready with a non-valent response, identifying precisely our explicandum, as a propaedeutic perhaps to the Socratic response of ‘problematizing the question’ in a search for a fuller, deeper and/or more relevant set of descriptions of what appears as an inherently dilemmatic situation – to which the best response is to redescribe, or, in the practical domain, otherwise alter the alternatives.”

The blurb on the back flap says that this is Bhaskar’s most accessible book, and unwary readers may think it is suitable as an introduction to philosophy. They would be wrong.

Someone whose striate cortex (primary visual cortex) has been damaged
or destroyed can sometimes identify the position and even the shape of light
stimuli without the aid of any conscious visual experience. Even when told
that they are giving accurate reports about the light stimuli, blindsight
subjects, as they are called, say that they are guessing. If sight or visual
perception were no more than an ability to process information about light
stimuli, then blindsight subjects could be said to see. If, on the other
hand, sight or visual perception requires visual experience in addition
to information processing, blindsight subjects are blind.

Is blindsight really sight or it is perception? This is the question
at the heart of a clash between computational approaches to perception and
what might be called phenomenological approaches – those that insist that
sight is not just processing information but an experience that everyone
who is not blind undergoes in most of waking life.

The two approaches are perhaps best represented in this volume by Michael
Tye (for the computationalists) and E. J. Lowe (for the other side). Tye
considers a wide range of sensory and perceptual states that allegedly consist
of something other than information, or of more than the information they
embody. He attempts to show that this alleged extra either eludes introspection,
or is conjured into existence by a bad theory of meaning or fallacious modal
reasoning.

I find his arguments unconvincing. I wonder, too, whether he gives a
fair description of the view his opponents hold. ‘Many philosophers,’ he
says, ‘take it to be evident that visual experiences have, over and above
their representational contents, intrinsic, introspectively accessible properties
in virtue of which they have those contents.’ The ‘in virtue of’ clause
gives him an easier target than he has a right to. Once the clause is eliminated,
the phenomenological position is pretty formidable; that is, it is possible
to describe conscious experiences without recourse to metaphysical explanation.

Lowe’s paper is more than a defence of the phenomenological approach
to the philosophy of perception. It contains a definition of visual perception,
and an argument for regarding sense-perception in general as necessary for
the formation of judgment and belief about the world. In connection with
the phenomenology of perception, Lowe appeals not just to the strong intuition
that the blindsight subjects lack something that is crucial to seeing. He
also points to the ways in which the vocabulary we use to report sensual
stimuli, such as ‘looks’ and ‘appears’, are as much about the experience
of the subject as the things reported on. I believe that he exaggerates
in claiming that these locutions count in favour of a modest sense-datum
theory.

Lowe thinks that the tendency to downplay visual experience among philosophers
and psychologists reflects a mistaken association of subjective experience
with ‘a forbidden Cartesian paradigm of mind’, which implies that consciousness
of an experience is axiomatic. But one does not have to be a Cartesian to
suppose that sight or visual perception has a phenomenology, any more than
one has to be a Cartesian to maintain that pain is necessarily conscious.

When Tye asks what the costs of believing in visual experiences (qualia)
are, his answer is not that the belief carries a lot of unwanted Cartesian
baggage, but that qualia bring with them puzzlement. ‘If there are visual
qualia and they are irreducible, then the ‘felt’ aspect of the visual experience
of blue is a matter of its having a special, nonphysical property . . .
Does this really offer us any enlightenment?’. As if the claim that there
are visual qualia and that they are irreducible was meant to be explanatory.
It is in fact a claim about the limits of explanation by reduction.

There is more in this collection than computation versus phenomenology.
J. J. Valberg and Paul Snowdon write about objects of perception. Papers
by Christopher Peacocke and Tim Crane try to throw light on the kinds of
nonpropositional and nonconceptual content that states of mind can have,
and there are good essays on an old question about sight and touch (Michael
Martin) and the relations between per-ception and action (Brian O’Shaugnessy).
Nearly all of the contributions are addressed to professional philosophers,
rather than interested psychologists or brain researchers. This is ironic
in a volume where so much concerns the assimilation of the philosophy of
perception to science.

Tom Sorell is a reader in philosophy at the University of Essex.