For much of my life, I treated sleep like loose change. Nice to have, but easy to misplace. Four hours on a good day, six if the world was kind. I wore sleep deprivation like a badge of honor. “I can function on four,” I would say, a little smugly. As if survival were the same as thriving.

And then came Why We Sleep by Matthew Walker.

I’ve long followed Sadhguru’s teachings. His take on sleep is different. Sleep, he says, isn’t the point. Restfulness is. If your system is well-aligned—if your food, breath, and emotions are in balance—you may need just three or four hours of sleep. Not as discipline, but as consequence. The body rests best when it’s in harmony.

For a long time, that was the goal. Maximize life, minimize idle time. In my circles, six hours was the upper limit. Anything more felt like indulgence.

But then I read Walker.

The book didn’t just inform me. It changed the way I saw rest. He lays out a case so thoroughly researched, so biologically intimate, that I found myself reevaluating years of habit. Charts of NREM and REM cycles. Experiments showing that a week of six-hour nights leaves you cognitively impaired. One line struck me especially:

If sleep were useless, evolution would have eliminated it by now.

I had always thought of sleep as the body’s repair time. But Walker flips the lens: it’s the brain that most needs sleep. NREM for memory consolidation. REM for emotional regulation, creativity, integration. This isn’t just rest. This is reconstruction.

If sleep were useless, evolution would’ve eliminated it by now. You are not looking for food or procreation and you are prone and vulnerable. Still, every species in the animal kingdom sleeps. It has to have something critical to add.

I saw the charts, I understood the architecture of REM and NREM cycles. I realized that cutting off any part of those cycles is detrimental. But what made the case for me, incontrovertibly, was the evolutionary sentence. It’s about survival of the fittest. And sleep has to add something to your being fit to survive, otherwise it wouldn’t be there.

So I made changes. I set my phone to amber after 9 PM. I stopped treating 2 AM as a reasonable bedtime. And for the first time in years, I let myself sleep in—without guilt.

Still, a question stirred beneath this newfound discipline. If Walker’s argument is correct, then how does Sadhguru’s make sense?

Because Walker stayed with me. Sleep is not optional. It is the very mechanism through which the brain resets, repairs, reimagines. And yet, there is evidence that deep meditative states mimic sleep.

Studies on Yoga Nidra, Vipassana, and deep meditation show brainwave patterns similar to those of early sleep: alpha, then theta. Some even touch delta waves—the signature of dreamless, restorative sleep. Long-term meditators show enhanced REM architecture. It doesn’t negate Walker. But it offers a glimpse of how Sadhguru’s claims might work—for a certain kind of practitioner.

So perhaps they’re not in opposition after all.

Walker maps the scaffolding of sleep. Sadhguru speaks to a path where restfulness reduces the body’s demands. One describes the descent; the other, the preparation.

And while the meditative traditions Sadhguru points to may offer an alternative path, I know I’m not there. I’m not an advanced meditator. I am, however, someone who values brain function. And if REM sleep takes time, if the deeper cycles come late in the night, then I’ll make time for them. No shortcuts.

Now I sleep. Deliberately, protectively. Not as surrender, but as strategy.

Some nights, I sleep eight hours and wake clear. Other nights, it’s less. But I no longer treat sleep as a luxury. It is a foundation. Have I arrived? Not yet. But I’m on the path—consciously.