CNBC’s Jim Cramer said Thursday investors risk missing some of the market’s biggest opportunities when they put too much weight on the past. The key, he said, is booking profits along the way.

“History doesn’t always repeat itself, it doesn’t always rhyme, and sometimes it’s impossible to make heads or tails of what’s going on,” the “Mad Money” host said. “Yet that never seems to stop the bears from invoking history as a way to scare you out of your stocks.”

Cramer said investors should learn from past market cycles, but warned that relying too heavily on historical comparisons can obscure what has fundamentally changed. He pointed to Nvidia, Cisco, and Workday as examples where he thinks skeptics are applying old lessons to new circumstances.

“There are always plenty of seemingly intelligent skeptics in any market. They rarely want to be called bears, just wise historians, or at least they fancy themselves as such,” Cramer said. “I can’t stand these people.”

With Nvidia, Cramer said skeptics have questioned the company’s new effort to create securities backed by computing capacity because semiconductors have historically depreciated quickly. However, Cramer argued Nvidia’s GPUs are different than chips from decades earlier, pointing to neocloud CoreWeave saying this week that its six-year-old Nvidia GPUs are being rented out through 2029, and at a higher price than before. Nvidia’s software updates are helping extend the useful life of these chips, CoreWeave CEO Mike Intrator said Wednesday on CNBC.

“There was nothing like that historically, so how can history repeat itself if the details are so different?” Cramer asked rhetorically on Thursday.

He also pointed to Cisco, whose stock collapsed roughly 90% after becoming the world’s most valuable company during the dot-com boom. When Cisco finally surpassed its dot-com-era stock price in December 2025, Cramer said skeptics warned history would repeat itself. Instead, he said the stock has climbed more than 40% since, reflecting how it is a changed company.

Workday is another example, he said. Shares have been pressured by fears that AI could disrupt traditional software companies, but he said reports that Silver Lake is in talks to take Workday private challenge the bearish narrative that these businesses are destined to lose value.

Cramer acknowledged the AI and data-center boom will peak at some point. His argument, however, is that investors shouldn’t avoid owning tech stocks in the meantime because previous booms eventually ended.

“That doesn’t invalidate all the money you can make in the data center before they peak,” he said.