What does it mean to call consciousness an illusion?
The claim sounds more dramatic than it is. Frankish's "illusionism" holds that conscious experience is misrepresented as having "phenomenal properties"—special felt qualities that seem to exist in an inner theater of the mind [1]. On this view, the illusion isn't that we have experiences; it's that we take those experiences to possess a private, ineffable something extra.
Frankish describes phenomenal consciousness as an "introspective illusion," an artefact of the limits of introspection [2]. In plain terms: when we look inward, we don't see a transparent recording of our mental life. We get a simplified, distorted report—and we mistake that report for the thing itself. The illusionist then swaps the famous "hard problem" of consciousness (how could physical processes produce felt experience?) for a more tractable "problem of illusion" (why does introspection tell us we have such experience?) [1].
Why would introspection mislead us about our own minds?
The argument leans on a critique of "qualia"—the supposed raw feels of experience, traditionally described as intrinsic (existing in themselves), ineffable (impossible to put into words), and subjective (accessible only to the person having them) [3]. Frankish argues that this "classic" picture can't serve as neutral ground for a science of consciousness.
His sharper move targets a watered-down version he calls "diet" qualia: qualia stripped of those three features in hopes of making them scientifically respectable. He argues this diet notion has no distinctive content—once you remove intrinsicality, ineffability, and subjectivity, no phenomenal residue is left [3][4]. What remains, he says, are "zero" qualia: our dispositions to judge that our experiences have classic qualia [3][4]. In other words, the felt mystery may be a habit of judgment rather than a feature of experience.
This is where the "Cartesian theater" worry enters. If we picture a little inner viewer watching our experiences, we build in the very thing illusionism denies—a place where phenomenal properties are displayed [1]. Frankish's reply to critics is that illusionism need not ignore the immediate data of consciousness; it reinterprets that data as a product of how introspection represents us to ourselves [1].
Does illusionism mean we're unfeeling machines?
A common misreading is that illusionists want to eliminate mind and consciousness altogether and picture us as unfeeling machines. Frankish explicitly rejects this caricature, saying he does not recognize it as his view [5]. His reply to critic Paul Stenner is that the disagreement rests on a distorted picture of what illusionism claims, and he uses the response to clarify both the view he endorses and the one he rejects [5].
So the practical upshot is narrower than it first appears. Illusionism denies a particular metaphysical picture of experience—one with intrinsic, ineffable, private feels—not the plain fact that we see, hurt, taste, and remember. The debate is about what kind of thing those facts are, and whether the "inner glow" is a genuine extra or a story introspection tells.
Is this settled, or still a live argument?
It is a live argument. Frankish presents illusionism as having strengths and prospects, and as gaining new impetus once freed from the metaphysical framework of realism—but the critical portion of his work is explicitly not aimed at refuting rival views or delivering a definitive argument for illusionism [1]. The claim is offered as a defensible position, not a proven result.
That matters for how to read the question. The honest answer is that consciousness could be an illusion in Frankish's specific sense—an introspective misrepresentation rather than a hidden inner substance—and that this reframing is argued to make the problem of consciousness more tractable [1][2]. Whether the illusion is real, and what exactly introspection is doing when it misleads us, remains contested rather than closed.
Sources used in this answer
Illusionism as a Theory of Consciousness. Part II
Illusionism claims phenomenal consciousness is illusory because experience is misrepresented as having phenomenal properties, replacing the hard problem with the problem of illusion.
Illusionism and its place in contemporary philosophy of mind
Frankish's illusionist theory holds that phenomenal consciousness is an introspective illusion arising from the limitations of introspection.
Quining Diet Qualia Part I
The classic conception of qualia cannot serve as neutral ground, and the watered-down "diet" notion has no distinctive content, leaving only "zero" qualia—our dispositions to judge that experiences have classic qualia.
Quining Diet Qualia Part II
Stripping qualia of intrinsicality, ineffability, and subjectivity leaves no phenomenal residue, so only "zero" qualia need explaining.
Illusionism is no trick
Frankish rejects the charge that illusionism eliminates mind and consciousness or treats people as unfeeling machines, clarifying his actual position in reply to Stenner.