When Think and Grow Rich was published in 1937, it became more than a bestseller — it became the operating manual for American ambition. Napoleon Hill distilled the mechanics of achievement into a formula that entrepreneurs still quote nearly a century later.

But buried in the book’s final chapter was something most readers skipped over: a warning.

Hill called it the sixth sense — a higher dimension of intelligence beyond desire, visualization and persistence. He hinted that success built on mental force without inner coherence could turn destructive. A mind powerful enough to manifest greatness, he suggested, could just as easily collapse in on itself.

Nearly 100 years later, his warning reads less like mysticism and more like a diagnosis of the modern entrepreneurial psyche.

The cost of success we don’t talk about

Entrepreneurs today live in a world that has industrialized Hill’s system. Hustle culture. Optimization. Personal branding. Infinite scale. An entire economy now runs on the belief that more effort equals more evolution.

But behind the highlight reels, many founders face a different reality. 49% of entrepreneurs reported having at least one lifetime mental‑health condition compared to 32% among comparison non‑entrepreneurs. Burnout is common and often unnoticed until it reaches a crisis point. Cognitive overload — the constant mental juggling of strategy, operations and people — can erode decision quality, a founder’s most valuable skill.

Even icons acknowledge it. Musk, Jobs, Bezos — all have spoken publicly about the personal costs of building transformative companies. We’ve mistaken motion for growth and ambition for evolution. Hill’s work was never a worship of hustle; it was an invitation to awaken a deeper intelligence. We mastered his tactics but ignored his frequency. We gained productivity and lost presence.

When achievement becomes identity, success turns hollow. The same drive that builds empires can quietly consume the person building them. Externally, the world is thriving. Internally, many entrepreneurs are bankrupting themselves.

Related: 5 Entrepreneurial Mindsets That Drive Success

The blind spot in 20th-century success psychology

Hill felt there was more to achievement than mindset, but lacked the scientific language to articulate it. He described “vibration,” “subconscious power” and the “sixth sense” like a physics he could feel but not yet measure.

He wasn’t alone. Breakthrough thinkers throughout history brushed against the limits of raw intelligence:

• Early AI pioneers warned that intelligence without consciousness magnifies human flaws.
• Einstein regretted that his equation paved the way for destruction.
• Tesla dreamed of free energy — and died penniless while his discoveries were weaponized.
• Even Musk warns that unchecked intelligence, human or artificial, could threaten humanity.

The pattern is consistent: capability without coherence leads to collapse. Hill glimpsed this truth. What he couldn’t articulate is what we can now describe: awareness that determines whether success elevates us or erodes us.

Related: Being ‘Busy’ Isn’t Helping You Be Productive — 5 Tips to Become Truly Efficient at Work

The real revolution in entrepreneurship

Hill’s legacy wasn’t ambition. It was awareness. He left a set of clues for a generation with the tools to decode them — and that generation is us.

The next era of entrepreneurship won’t be led by the people who work the hardest or think the fastest. It will be led by those who operate with coherence — leaders who master energy as well as strategy.

These are the founders who can:

• Scale impact without fracturing themselves
• Innovate without self-sacrifice
• Build wealth that sustains instead of depletes
• Create organizations that restore rather than extract

Because the future won’t belong to the busiest minds. It will belong to the most coherent ones.

Perhaps the next revolution in business isn’t about creating more wealth. It’s about learning how to hold it — without losing ourselves.