The LRAD, or Long Range Acoustic Device, was first used in 2009 to control protesters at the G20 summit in Pittsburgh. Since then, it has been purchased by more than 60 countries to disperse demonstrators. Originally developed to deter pirates at sea, it has been notoriously used by Japanese whaling fleets against Sea Shepherd Conservation boats and helicopters. The military-grade device can project voice messages and eardrum rupturing “alarm tones” over a distance of two miles or more via a 30- to 60-degree beam.

The ACLU opposes the use of LRAD on First Amendment–protected protesters because of its chilling effect on free speech. “I’d rather be tazed, shot with a rubber bullet, maced, and then kicked in the balls than have my eardrums erupted,” an anonymous protest veteran told Digital Justice. LRAD was recently employed at Standing Rock, against water protectors attempting to save the reservation’s water source by halting construction of the Dakota Access Pipeline, which is set to run beneath the Missouri River. LRAD’s effect on people is devastating. But in a moving act of cultural transformation, the art collective Postcommodity is using LRAD in a radically different manner. The innocuous-looking gray LRAD speakers are installed in Athens, Greece, and the more softly pitched acoustical beam is directed at the archeological site of Aristotle’s Lyceum. Here, LRAD is used to speak to the origins of western civilization, not in weaponized tones, but in the language of the human spirit.

I met with Postcommodity artists Raven Chacon, Cristóbal Martínez, and Kade L. Twist at Bockley Gallery during the opening of an exhibition based on an earlier project, or ceremony, Repellent Fence (2015). I had never met Postcommodity before, but as they talked about the documenta 14 project in Athens, something switched on for me. It is unusual to be simultaneously moved, spiritually shaken, and visually and/or intellectually seized by an art installation. Good pieces of art get to you as who you are. Great ones speak to you as more than you are. They direct you to an area of thought and emotion where you want to express something beyond your grasp.

Aristotle’s Lyceum was founded in 335 BC, and as a school it fostered such intellectual inventions as inductive and deductive reasoning and organized scientific inquiry. The Lyceum was excavated in 1996, and today it is a historical park and an archeological site, open to the public. LRADs, placed by Postcommodity on the rooftops of the Athens Conservatoire of Music and Theatre and the Hellenic Armed Forces Officers’ Club, currently broadcast the voices of immigrants. In quiet song journeys, narratives of forced displacement, opera and silence, Postcommodity confronts the genesis of western philosophy. In its current iteration, western civilization includes runaway corporate capitalism, so in effect western philosophy has resulted in massive global destruction. An unrestrained free market has thrived on carbon emissions, causing climate change. And climate change has in turn caused droughts like the one that displaced Syrian farmers to cities, which caused desperation and unrest, answered by genocide, which then initiated the largest human migration in history. Unprecedented famines and water shortages are ravaging the Sudan. More than 65.3 million people are now displaced, most from Syria and Somalia. Distressingly, 51 percent are children, many of them separated from parents or traveling alone. They leave behind everything and go where there is nothing for them. They travel with only their stories and their songs.

People who have been subjected to LRAD report its haunting effect. Sounds traveling via the directed beam create phantom speakers. A voice, for instance, seems to emerge from an invisible person right in front of you. The LRAD sound beam “gets in your head.” For 100 days in Aristotle’s Lyceum, ghosts are speaking to ghosts. Restless contemporary spirits are interrogating the dead. Instead of broadcasting military orders, the art installation’s LRAD broadcasts questions.

How has deductive reasoning resulted in the monster of the military state? Can you see the connections between Standing Rock and all else that lives and moves? Why is scientific inquiry useless in arguing for the fate of the world? How did western thought and the fruit of western thought beget the invention of weapons systems that can demolish everything we love? How and why have so many humans been driven to wander the world?

Postcommodity often mentions ceremony in describing their work. Ceremony in Native American life has to do with addressing the mysterious in ritualized ways, bound up tribal history, and language. A ceremony usually involves a transformation. A water drum once ceremonially assembled becomes human. A sacred pipe once blessed, dedicated to each direction, and lighted, carries prayers to the Creator in its smoke. A person becomes known to the spirits by a newly dreamed name. In the documenta 14 installation, a sound weapon is transformed into a delivery system for spirituality. Those who were at Standing Rock speak of the instant agony produced by LRAD bursts of sound, typically between 150 and 162 decibels. The threshold level for hearing damage is 85 decibels. Extremely loud, sudden noises can cause permanent cellular damage to the inner ear, and even to the human brain. Postcommodity’s work is to heal that damage, to inflict, instead of pain and loss, complexity, meaning, and gorgeous sound.