In 2006, Alex Miller was a US Navy IT specialist, tracking pirates off the coast of Somalia. Two years later, he didn't have a home.

David Harvey’s work over the years has looked at the economy in radical ways, linking how we earn and spend with, say, geography. Among his fresh frameworks is something called "spatial justice." Steve Paulson asked Harvey what he means by that.

The story of Mazotec healer Maria Sabina is a notorious example of how psychedelic enthusiasts have exploited the knowledge of Indigenous cultures they don’t really understand.

Pharmaceutical companies have a long history of hunting for medicinal drugs, often in Indigenous cultures. Historian Lucas Richert tells the story of how one company went bioprospecting for peyote.

Over four decades, philosopher Nancy Fraser has worked to expose the deep roots that connect all the crises of our time: racial violence, environmental devastation, the impoverishment of families, challenges to democracy. Think of each as the toxic byproducts of capitalism.

Tall Paul is an Anishinaabe and Oneida rapper enrolled on the Leech Lake reservation in Minnesota. His new album is called "The Story of Jim Thorpe." Charles Monroe-Kane spoke with him about Thorpe’s legacy, sports and hip-hop.

Math superstar Jordan Ellenberg reveals the geometrical underpinnings of pretty much everything — from pandemics to voting districts to the 14th dimension. If geometry is indeed "the cilantro of math," Ellenberg could convert even the most die-hard hater to the joy of shapes.

Scholar Brian Muraresku makes the controversial argument that the famous Eleusinian Mysteries were fueled by a psychedelic beer.

"On Immunity: An Inoculation" author Eula Biss recommends a memoir in which author Maggie Nelson asks questions that bend conventions about gender, sexuality, motherhood, family and identity itself.

Our producer Charles Monroe-Kane has a passion for ravens.  The raven has meaning for him from legend and art, to the point where he’s had one tattooed on his forearm.

Stephen Alvarez — a National Geographic photographer and founder of the Ancient Art Archive — has spent years documenting ancient rock art around the world. He takes Steve Paulson on a long hike in the Cumberland Plateau, where they find an "unnamed cave" with 2,000-year old engravings.

In the years when psychedelic science had been shut down, Amanda Feilding helped jump-start research into altered states of mind. Today, she's in her 80s and remains active in psychedelic research with her Beckley Foundation.

For years, Robin Carhart-Harris dreamed of using brain scans to study people on LSD. He’s gone on to conduct pioneering research on psilocybin, and he’s formulated a theory of the "entropic brain" to explain what happens during psychedelic experiences.

Steve spoke with Yale astrophysicist Priya Natarajan about the search for invisible parts of the universe, dark matter, and the mind-boggling nature of black holes.