If you need to tackle an improbable challenge, the right mindset — “a special kind of optimism” — can help, according to Moderna co-founder and chairman Noubar Afeyan.

The billionaire called it “paranoid optimism,” and said he’s “always practiced” this mindset during a commencement speech at the Massachusetts Institute of Technology last month. It involves “toggling back and forth between extreme optimism and deep-seated doubt,” so you can encourage your own inventiveness while still maintaining a sense of reason, he said.

“I’m utterly unreasonable and an eternal optimist,” added Afeyan, who completed a PhD in biochemical engineering at MIT and served as a lecturer there for more than a decade at the Sloan School of Management.

Specifically, Afeyan — who has an estimated net worth of $1.5 billion, according to Forbes — said that “extraordinary change agents” take three actions to achieve what seems impossible:

  1. They imagine.
  2. They innovate.
  3. They immigrate.

Imagination plays a crucial role “in accomplishing impossible missions,” Afeyan said: You typically need to think creatively to come up with new, original ideas.

Creative thinking may feel easier said than done, but experts recommend a variety of methods to spark your imagination — including a five-step strategy called “design thinking,” which Bryant University psychology professor Allison Butler described to CNBC Make It in January.

“The idea is that it seems like a checklist: Watch people, learn from them, craft insights, brainstorm great ideas [and] start to prototype,” Butler said.

Imagination then sparks innovation, or “imagination in action,” Afeyan said.

Turning any particularly imaginative idea into reality may be challenging, he said: “Leaps often involve unreasonable or even seemingly crazy ideas … But ask yourself one central question: Why do we expect extraordinary results from reasonable people doing reasonable things?”

Lastly, Afeyan espoused the benefits of immigration — or, in other words, getting outside your comfort zone. In his case, it was literal: Afeyan was raised in Lebanon to an Armenian family, before moving to Canada and then Massachusetts. But any experience breaking new ground should metaphorically count, he noted.

“Whether you grew up in Cambodia, or in California or right here in Cambridge, you can [intellectually] immigrate,” Afeyan said. “You need to leave your comfort zone, to think in new ways, to acclimate to the unfamiliar and embrace uncertainty.”

Afeyan has firsthand experience tackling a daunting mission: Under his watch, Moderna began developing one of the world’s first safe and effective Covid-19 vaccines in the earliest days of the virus’ transmission, before much of society had retreated into quarantine and Zoom calls.

Practicing all three actions on Afeyan’s list means you’ll be “destined to a life of uncertainty” — which, though uncomfortable, can help you achieve great career heights, he said.

“It’s where you need to be,” Afeyan said.

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