There was also another data point that shocked Cramer. Two days prior to the Chinese bottom, oil stopped going down. Black gold hit $38 a barrel that day and hasn't looked back since.
And while Cramer does not know whether China or oil had more of an impact on the industrials, he does know that every single chart of the major oils bottomed. Industrials and old tech stocks have been headed straight up since that time.
Additionally, there has been no similar correlation to high growth tech stocks or the biotechs. The bottom was limited only to the oils and industrials. Meaning, the cyclical stocks are the ones roaring back.
"To me, the strength in the industrials and old techs is all about China, which makes for a more compelling view of what is happening right now," Cramer said. (Tweet this)
And most interesting to Cramer is that the bottom in oil and industrials has been almost totally unheralded because no one believes that the bottom in the Chinese stock market was real.
But when Cramer stepped back, he saw it as clear as day.
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The "Mad Money" host believes that both the bottom in industrials and the bottom in oils are lasting. If that is the case, then anyone who has not participated in the oil and industrial rotation could get run over. Those who have been buying into the consumer packaged goods will turn out to be right.
"I will stick my neck out, though, and say both trends are for real," Cramer said.
If he is right, Cramer anticipates that investors will have radical rethinking of the stocks they choose for their portfolios going forward for the rest of the year. That could impact everything from General Electric to companies linked to the Chinese consumer and those stemming from an emerging marketplace.
That means it's time to start your engines; in Cramer's book, the oils and industrials could be the major winners for the rest of 2015.