"I don't understand why people attack this car. It is made in America, by Americans. It is built local. You know we are becoming like the British — we like noble failures more than we reward success," Leno said.

Leno appeared on CNBC's " Squawk on the Street " after ringing the opening bell at the New York Stock Exchange Tuesday to celebrate " Jay Leno's Garage ," and spoke with Cramer on his opinion on Tesla . But it was the acknowledgement of the undercurrent of gloom within the American business foundation that stuck with Cramer.

"Every once in a while you get a wake-up call about how gloomy things actually are out there. They come in all shapes and sizes. Today's came in the form of Jay Leno," the " Mad Money " host said.

Jay Leno 's commentary on the state of business in America on Tuesday was a wake-up call for Jim Cramer.

Leno compared Tesla CEO Elon Musk to great car legends such as Thomas Edison or Henry Ford for his ability to produce cars against all odds.

"I think Jay has a pretty good point. And he is dead right when he says 'I don't understand why we don't celebrate entrepreneurship more and success in this country'," Cramer said.

While Cramer still maintained that he cannot value Tesla's stock, he did recognize that many underestimate the fact that Tesla has long waiting periods to buy the car, whereas most other cars can be bought on demand and likely at a discount.

Leno added that he believes engineers will save the world one day, stating that Los Angeles has millions more cars than it did in 1972 and has less smog now.

"We often forget that there is such thing as progress, and progress can create a better world. Progress is also the secret propellant of stocks," Cramer said.

Thus, if the success of entrepreneurs like Elon Musk is overlooked, there is clearly a negative backdrop to the stock market. The gloom has permeated stocks for so long; many investors forget that anything can even go up.

"I suggest you use Jay's words, not as a clarion call to go buy stocks, but as a reminder that getting too pessimistic is at odds with reality, and that progress is worth celebrating," Cramer said.

So for those investors that abide by the "sell in May" or any other month mantra, Cramer reminded them that engineers have done amazing things, and companies still create incredible products. Stocks, too, can go higher on this simple notion of progress celebrated by Leno.