It was a day that was eye-opening in every respect, and an evening that ended with a strong case for closing them.

Day One of Fortune’s Brainstorm Health revealed a way to rewrite pain (through virtual reality), edit our genetic destiny, and translate the frailty of old age into a kind of youthful progression into maturity. We had some appropriate panic over pandemics to come and were shocked—many of us, anyway—by what turns out to be a substantial risk factor for getting Alzheimer’s disease: being a woman. We learned about the virtue of the blockchain in healthcare, the need to break old chains in drug development, and what happens when you create a chain of new partnerships with your trusty supercomputer. We had an extraordinary guided meditation and mediated on the guidance of many.

Yes, it will take some measure of these newsletter essays to fully unpack all of the insights and wisdom that emerged from the first day of our inaugural Brainstorm Health. And I will do my best to follow up on these great panel discussions in the weeks ahead. But it’s now nearly midnight and time to celebrate sleep.

That, indeed, was the resonant theme in this evening’s dinner discussion between Brainstorm Health co-chair David Agus and media maven Arianna Huffington, who has just launched a company dedicated to promoting wellness in the workplace: Thrive Global.

“We are so used to being perpetually tired,” said Huffington, that we don’t know when we’re crossing what she calls “the red line”—the point of exhaustion. “We need to help people understand the signals” before they get there.

“If you think about it,” she told the rapt audience, “we all take better care of our smartphones than we take care of ourselves. I bet everybody here knows approximately how much battery life their phones have left.” And yet, we rarely have that kind of awareness of our minds and bodies.

Huffington pointed out that if you type the words “Why am I…” into Google, the first autocomplete suggestion it offers is: “Why am I so tired?” That, she said, is a window into a culture that inappropriately measures success by degrees of overwork: “It is not accurate that, in order to succeed, you have to burn out. It is not accurate that, in order to be super-productive, type A, driven people, we need to be always on and sacrifice our health and well being.” We need to change the mindset that has us believing that.