There is, it seems, no mechanism in the mind or the brain for ensuring the truth, or at least the veridical character, of our recollections. We have no direct access to historical truth, and what we feel or assert to be true (as Helen Keller was in a very good position to note) depends as much on our imagination as our senses. There is no way by which the events of the world can be directly transmitted or recorded in our brains; they are experienced and constructed in a highly subjective way, which is different in every individual to begin with, and differently reinterpreted or reexperienced whenever they are recollected. (The neuroscientist Gerald M. Edelman often speaks of perceiving as “creating,” and remembering as “recreating” or “recategorizing.”) Frequently, our only truth is narrative truth, the stories we tell each other, and ourselves—the stories we continually recategorize and refine. Such subjectivity is built into the very nature of memory, and follows from its basis and mechanisms in the human brain. The wonder is that aberrations of a gross sort are relatively rare, and that, for the most part, our memories are relatively solid and reliable.

We, as human beings, are landed with memory systems that have fallibilities, frailties, and imperfections—but also great flexibility and creativity. Confusion over sources or indifference to them can be a paradoxical strength: if we could tag the sources of all our knowledge, we would be overwhelmed with often irrelevant information.

Indifference to source allows us to assimilate what we read, what we are told, what others say and think and write and paint, as intensely and richly as if they were primary experiences. It allows us to see and hear with other eyes and ears, to enter into other minds, to assimilate the art and science and religion of the whole culture, to enter into and contribute to the common mind, the general commonwealth of knowledge. This sort of sharing and participation, this communion, would not be possible if all our knowledge, our memories, were tagged and identified, seen as private, exclusively ours. Memory is dialogic and arises not only from direct experience but from the intercourse of many minds.

I wish I could leave it at that. But the problem with simply saluting Ai as a political activist is that he insists on pleading his case in the art museums. The Hirshhorn exhibition—which originated at the Mori Art Museum in Tokyo in 2009 and will conclude a five-city North American tour at the Brooklyn Museum in 2014—takes its title from a 1964 painting by Jasper Johns, According to What. The Ai Weiwei who admires the conundrums of Jasper Johns, that most beloved of contemporary aesthetes, is very much in evidence at the Hirshhorn in a work such as Surveillance Camera, a white marble simulacrum of one of the tools of the police state (which is also ubiquitous in democratic societies). Whatever the message Ai means to send with Surveillance Camera—and the Chinese autocrats certainly have many cameras trained on Ai—it is notable mostly as an example of made-to-order ironic neoclassicism, and for all intents and purposes it is indistinguishable from the marble rendering of a garbage can by the New York bad boy artist Tom Sachs. (Some may recall that Sachs got the gallerist Mary Boone into trouble a few years ago when he placed live ammunition in a vase in her gallery and invited visitors to take cartridges as souvenirs.) With Ai, one wonders where the political dissent ends and the artsy attitudinizing begins. At least that was what I found myself wondering at the Hirshhorn, where Ai marries his somber subject matter with a slyly luxurious less-is-more aesthetic. I suspect that this synthesis is part of what museumgoers find so satisfying about the show. Some visitors seem awfully pleased with themselves, as if by coming to see Ai Weiwei at the Hirshhorn they are doing the right thing and killing two birds with one stone: acquiring both art cred and political cred.