Bernard Tyson had a vision for the future of health care. He also had a gift for getting to the heart of the matter.

“We cut off the head from the body,” he’d say.

Tyson, who died unexpectedly on Sunday, believed our health care system had a crucial design flaw: it separated our physical health from our mental health. As CEO of Kaiser Permanente, he was a relentless advocate for ending this separation and replacing it with a whole human approach to health.

He was outspoken about ending the stigma around mental health and broadening our definition of health. And at a time when the conversation around health care tends to focus on minutiae about financing, Tyson had the boldness to speak to something larger — not only diagnosing the problem, but committing himself to surfacing preventive solutions and changing the system.

In recent years I had the privilege of getting to know him and seeing his passion up-close. Again and again, he would speak of reconnecting the head and body, remaking our approach to health care and reforming a system that too often deprioritizes and silos mental health issues.

As Clifton Leaf writes in Fortune, “It was a simple, even obvious notion, perhaps — and yet this was a dramatic departure from the way health care has been conceived in America.”

With his relentless advocacy and leadership, Tyson pushed the boundaries of how we define health. He believed we were severely limiting our understanding by operating with a simplistic, purely physical approach to health. He understood that about 90% of health care costs are related to preventable chronic diseases and mental health conditions. And he knew that the solution depended on treating not just individuals, but communities. Under his leadership, for example, Kaiser Permanente has funded studies on how to reduce gun violence. As Tyson said, “People need to be safe in the places where they live, work, learn and play.”

The list of his contributions and boundary-pushing efforts goes on. He was among the first to bring the mental health conversation to the World Economic Forum in Davos, with a 2017 panel called “The Silent Epidemic.” And in 2004, before he became CEO, he launched Thrive, a Kaiser Permanente campaign prioritizing preventive care and empowering people to focus on what he called “total health”: a whole human approach including mind, body and spirit. We often joked that we had both landed on the word Thrive to capture this whole human sense of well-being and our collective need to shift from surviving to thriving.

The last time I saw Tyson was in October, at the Time 100 Health Summit. Over lunch, I told him about Thrive Global’s new initiative timed to World Mental Health Day, and about Thriving Mind, our digital mental well-being program that speaks directly to people navigating the stresses and demands of the 21st-century workplace. He fired off ideas on how we could join forces and have even more of an impact. We scheduled a meeting in his office in Oakland on November 20th to go deeper.

Today, as we reflect on Tyson’s life and legacy, I count myself as one of many inspired by his leadership and grateful for his friendship. His blueprint for a whole human approach to health is one we can all build on.

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