At different times, Cramer says the advance or decline in a certain stock can provide meaningful insights into the broader market.
And right now, Cramer's go to stock is GE.
Why is this stock the key to the market's next move? In part it's due to a recent downgrade from Oppenheimer in which the firm suggested 2014-2015 would be a transitional period for earnings growth.
Cramer interpreted the downgrade to mean GE was out of catalysts.
Johnny Stockshooter | Age fotostock | Getty Images
"If Oppenheimer is right with its downgrade I take it to mean that the market is reaching the end of the period of industrial outperformance that began with the strong labor reports from the fourth quarter," Cramer explained.
That's critical, because as Cramer explained earlier in the week, immediately following recent jobs numbers many industrial stocks have rallied.
Cramer believes those rallies reflect the view that better-than-expected jobs numbers are interpreted on Wall Street as a sign the economy is getting stronger and stronger.
If that thesis holds, then effectively, the price action in GE reflects optimism or pessimism about global growth.
And although Cramer concedes pessimism could prevail and GE shares could run out of gas, he's inclined to believe optimism will win the day and therefore a rally is far more likely
Read More from Mad Money with Jim Cramer
Blue chip bull? Cramer's Dow predictions
Cramer fired up about smokestacks
First day decline, sign of trouble?
"In my humble opinion, I believe Oppenheimer is wrong," Cramer said. "I think GE could trade $40 with a renaissance in industrial production returning GE to greatness."
What's the bottom line?
Perhaps an old ad slogan with a new twist sums it best – as GE goes so goes the market.
Call Cramer: 1-800-743-CNBC
Questions for Cramer? firstname.lastname@example.org
Questions, comments, suggestions for the "Mad Money" website? email@example.com