Marcuse sees a vital role remaining to aesthetics. It has not lost its revolutionary power, 'crippled by [philosophy's] resignation before reality'.
Specifically dismissing the deterministic idea that art merely reflects society, Marcuse observes that art "opens a new dimension of experience" (7).
Although not stated, this concern with liberating human sensitivity through
art is unquestionably connected to Marx's own insistence, in the Economic
and Philosophical Manuscripts, on the "emancipation of the senses" and on
the unfolding richness of the "subjective human sensibility". By relating this
sensory liberation to the pleasure principle, however, Marcuse interprets art as
much more than a process of aesthetic refinement leading to human wholeness. Rather, Marcuse sees art as an explosive force giving rise to another reason, another sensibility, capable of subverting the dominant consciousness. Thus, art simultaneously enhances our perception of things and causes us to come into conflict with them. This process involves what Marcuse labels "the hidden categorical imperative of art": art's realization lies outside of itself,
even though the conception of art goes beyond all else (57). In contradistinction to orthodox Marxists, Marcuse contends that the political potential of art resides in the aesthetic form, supposedly autonomous, but not in any tendentious content that would restrict art to "reality" while forcing the artist to "record" it. (David Craven, review of H. Marcuse, 'The Aesthetic Dimension: Toward a Critique of Marxist Aesthetics', Theory and Society, Vol. 11, No. 1 (Jan., 1982), pp. 109-10.)
There is no suggestion here that aesthetic theory cannot 'generate any new insights, only destroy old ideals of beauty' : and Marcuse was writing long after Adorno's 1966 Negative Dialectics.