When Mark Cuban says something bullish, Jim Cramer listens, especially because the billionaire investor is known for being strategically skeptical.

"So I was blown away yesterday when Cuban came on 'Fast Money' and was asked whether it bothered him that four stocks — Amazon, [Alphabet's] Google, Facebook, and Apple — now account for $2 trillion in market capitalization. His answer? 'In terms of stock price?' he said. 'No, they are all undervalued.' Undervalued? Holy cow!" the "Mad Money" host said.

Cuban's reason for being bullish is simple: the tech giants are well positioned to expand and do business in the areas of machine learning and artificial intelligence.

"I couldn't agree more," Cramer said. "One of the reasons we keep going out West so often is because, like Mark Cuban says, 'I need to retrain my brain because I want to see the business application.' Cuban knows how powerful these tools are for doing business better, and, of course, unfortunately, with fewer people."

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Cuban's largest position is Amazon. He called the company "the ultimate A.I. company" and "the ultimate start-up," applauding the e-commerce colossus for knowing what people will need before they need it.

To further prove Cuban's point, Cramer turned to retailer Nordstrom's Thursday post-earnings conference call. Management cited dramatically lagging same-store sales of negative 6.4 percent, and said they noticed patterns of shoppers migrating to full-price stores instead of their discount Nordstrom Rack brand.

"I found myself thinking Amazon is so much more sophisticated about its customers, it could probably predict exactly what age, what gender, who would go next door, at what time, how much they'd spend, and then they'd give you a coupon before you went," Cramer said. "I always felt that Nordstrom has been fighting its cross-town rival in Seattle with one arm tied behind its back because of Nordstrom's asset-heavy model. Now I think it's both arms."

Cramer also liked the "Shark Tank" judge's arguments about Facebook and Google, adding that he was shocked when Facebook's stock did not rally with the stock of its rival, Snap.

"I think the copycatting of Snapchat by Instagram is really what's behind a lot of what now looks to be the reason why Snap failed to deliver the robust revenues so many people were expecting," the "Mad Money" host said.

Finally, Cramer said Alphabet is second only to Amazon in the artificial intelligence arena, as the company is developing AI capabilities for cars and robots, not only for its search engine.

And while Cuban did not put Apple in the same class as the rest, Cramer noted that the investment guru did not make an argument against it.

"All in all, if you're competing against a company that has deep machine learning and you do not have artificial intelligence going for you, then your fate will be like these retailers we see on our screens and the forecast will be in the vernacular of Mr. T: Pain!" Cramer concluded.

Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."

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