Carl Andre has used his sculpture to focus one of the broad tacit themes of modern art. That theme is the understanding that "art" does not exist without some commitment on the part of its spectators.
Andre reduced the terms of his sculpture to the point where nothing internal to the work seems to identify it positively as part. To people accustomed to thinking of themselves as passive respondents to solicitations made by art objects, Andre's work seems reduced beyond the point of non-existence as art. In fact, one sense of the term "minimal," so often applied to Andre's work, is "minimally difderentiated from non-art." People seeing his sculpture for the first time frequently become preoccupied with the question of how it is to be recognized as art when it lacks technique, expressiveness, personal style, and decorative qualities. But one thing Andre would have us understand by his reductive aesthetics is that we do not "recognize" something as art the way we recognize the sound of a clarinet or a friend's face in a snapshot. The issue here is not one of recognizing a novel item as an instance of something experienced previously. Rather, we recognize something as art more in the way we recognize another person's right to privacy or his rationality. We cannot make the latter kind of "recognition" without commitment, that is, without knowing we've made a choice in the process.
The conventional view of art experiences is that they depend mostly upon the artist's activity, on the way he inscribes it in what he makes. Andre has taken sculpture to reductive extremes partly to correct this view, to make us sense that our art experiences (and implicitly any experience) depend more upon our own activity, and on whether we know it for what it is, than we are accustomed to think. One of the most striking aspects of his work is its stillness. The work is so inert, so free of personal inflection, that we cannot speak unselfconsciously of its acting upon us. In the presence of Andre's sculpture, it is apparent that you and others act, while the art object "just sits there." Implicit in the acceptance of Andre's work as art is the task of speaking differently about what happens between people and things.
"Twelfth Copper Corner" is a characteristic Andre sculpture in several respects. It is an ordered array of industrially processed material units, square plates of copper, laid flat and unfastened on the floor so as to fill the corner of a room. (He often uses materials such as copper, zinc, and lead because these metals, being chemical elements, set a kind of logical limit to his reductive thinking.) The work is flat and horizontal in part so that it can be walked upon by the spectator. By inviting our physical entry into his work. Andre invites us to confront our assumptions about how and why a work of art is to be valued. To walk upon his sculpture is to confirm that no mysterious internal quality determines that it is "art."