Tim Noble and Sue Webster

If the seasonal pull exerted by thousands of teeming lights seduces holidaymakers and tourists to flutter like moths up and down the salacious promenades of Blackpool, or to cruise the super-myriad light-shows that illuminate downtown Las Vegas, then, one might argue, these melodramatic and gauche displays of raw metaphysics are proof that the aesthetic sublime still holds us captive.

Plato argued that it is not only the task of artists to transcend the gloomy world of mere appearances, it is up to them to pierce our grim reality with sparks of metaphysical essence that transcend the mire of terrestrial life.

So what better role model than effervescent Southend-on-Sea, contend Tim Noble and Sue Webster, where the neon refractions and autistic animations of tinsel-town Arcadia represent a fully computerised electronic sublime - readymade, plugged-in and lit up, twinkling and blinking in sequential pulses that couldn't fail to make Plato's capillaries blush in disbelief.

In Plato's Republic we are drawn to the image of Man shackled in chains to face the far wall of the dark cavern in which he finds himself imprisoned. Outside, illuminated by vivid flames, phantasmatic creatures carrying sculptures and effigies dance across the cave's threshold to cast shadows and vague silhouettes onto the back wall. We are enslaved, Plato tells us, to the inferiority of indirect phenomena; only through the play of art and poetry, represented by anecdotal silhouettes and unappreciable casts, can we hope to detect the slightest essence of metaphysical truth; only the enlightening flame of art can save us from the concrete fetters of bland physical matter and base thoughts.

It demands little evidence to realise that Plato's notoriously literal metaphoric illustration of appearance and essence has scoured its effect upon the collective artistic psyche; causing shadows and lights of all description to flicker and creep inside the cavernous interiors of blacked-out galleries everywhere. Yet Noble and Webster's contribution to the dubious Platonic light/shadow-genre is enmeshed both in self-doubt and in the cautious irony that self-doubt engenders; since, if they seem to be aiming to incorporate the usual procession of humanist essences that have been so earnestly flogged to death and pimped out as the sincerest of sentiments - of love and death ad infinitum - then the sheer libidinal Wattage of Noble and Webster's illuminations threaten to solarise the very heart of the Platonic soul, which, in Toxic Schizophrenia (1997), finds itself stabbed and reduced to a vacillating digitised grid of little coloured bulbs that fills and empties itself of blood.

Similarly lurid, the self-replenishing golden crucible of Excessive sensual indulgence (1996), gushes with crystalline droplets that only require us to be fascinated with the infinite circulation of its spectacular effect. A bleeding heart emblem and a golden fountain may not have too much thematic content per se (unless, of course, you're a sailor or crusader, respectively). It is in the resolutely narcissistic flexing of the spectral effects lifted from seaside illuminations and not the content of the work itself that fuses the viewer's expectation for an edifying metaphorical return for their time. And because the content could appear largely arbitrary, and the essential aesthetic aim so resolutely low, Noble and Webster's Platonic ideals are sadistically benign enough that we begin to waver in our belief that there is anything at all beyond these digital sequences that blink in and for themselves. We are merely experiencing pulsing lights that have short-circuited the metaphoric obligation to channel the viewer's gaze towards a higher aesthetic end - happy instead to watch the auto-erotic display tickle itself pink, red, blue, yellow and orange.

If doubt remains, the audible clang of Noble and Webster's metaphoric chains link up much too simplistically to allow any residual metaphysical payload the super-heavyweight status it might otherwise expect in more artistic hands. In this sense it is metaphysics itself that threatens to become fettered in plastic chains and set inside a brightly-lit cell to squint at the blinding appearances and smart at the obliterated essence.

The most precarious and interesting work, Miss Understood and Mr Meanor (1997), is a textbook emulation of Plato's phenomenological cavern. In a darkened room a projector casts light onto two separate assemblages of accumulated trash that look like wasp's nests perching on two vertical wooden poles. Deft manipulation of the mass of assorted textures (a broken plastic doll, a disposable lighter, a condom), causes immaculate profiles of the artist's heads, decapitated and impaled upon skewers, to be cast onto the wall.

On first inspection, the alchemic process that transubstantiates crappy-plastic into beautiful-shadows whiffs of Platonic idealism. As with the two accompanying light-works, we might detect the malignant presence of a value-machine that plunders seaside-treasure and appropriates ersatz debris in order to magic them into transcendent bourgeois wares. Even the critical incorporation of kitsch as a counter-cultural value does little more than intravenously inject bloated sophisticates with the presentation of more matter to redigest. After all, kitsch is nothing but the reification of another's detritus, the regurgitated splutter of cast-offs recycled through the mercenary taste-glands of de-constructive vultures. Luckily for us homeless pessimists, Noble and Webster's aesthetic sublime is considerably less gushing than it is gushing with digital blood. The sight of the ameliorated silhouettes of the two artist's dead-heads reminds us, as Kant warns, that it is an oversight to assume that the aesthetic sublime should be an entirely welcome or even human experience at all - that vampires and ghouls share the same noumenal habitat as beauty's essence.

Noble and Webster's aesthetic nihilism seems to sidestep the misapprehension that metaphysical idealism can be fatally wounded. Instead, like all persistent misanthropes, they simply reselect 'sincerity' for the odd special occasion when they might feel like wheeling its carcass out and stepping on its toes.