Jim Cramer has survived so long on Wall Street for many reasons, but the most important one is because he sticks by his rules of investing. One of his top rules is discipline trumps conviction.
"Rules that have kept you out of trouble have to be obeyed. Which is why, despite the pullback today…I can't pound the table on buying anything, because the S&P oscillator that I've followed for decades is now in overbought territory, which tells me we are due for some pain," the "Mad Money" host said.
The Standard & Poor's oscillator is an indicator that Cramer follows, which is a short-term measurement of current market sentiment. It is typically used to indicate how overbought or oversold the market is.
Right now, Cramer sees that the market is linked to three specific inputs. Stocks have tended to go higher if these three inputs are in the bulls' favor: a weaker dollar, higher oil and a stronger Chinese market.
"Now, let me say from the get-go that I may not necessarily agree that these inputs should cause a rally," Cramer said.
In fact, Cramer thinks that higher oil prices are bad for the consumer because it means lower savings in their pocket and lower consumption. It also means higher cost for most businesses, since only 10 percent of the directly benefits from more expensive crude.
However Cramer's opinion does not seem to matter right now, because there is a strong correlation between higher oil prices and higher stock prices.
The Chinese market flying higher should not matter at all, Cramer said, because the Chinese government is manipulating the market. But again, that didn't seem to matter as U.S. stocks were bought when the Shanghai Composite went higher.
The only input that made sense to Cramer was the weaker dollar, because the earnings of U.S. based international companies are hurt by a strong dollar. That is why ultimately the greenback matters enormously for the trajectory of the market.
So, if all three of these inputs are flashing green, as they were at one point on Tuesday, why does Cramer not want to use the weakness as a buying opportunity?
Because of the S&P oscillator.
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Cramer has watched the oscillator go up every night for the past few days, and there are levels where he gets cautious. Typically, anything above a five will be a red flag for him, and anything above 10 is an extra warning. On Monday night, the oscillator hit a 10, which is the equivalent of a danger zone for Cramer.
Historically, when the oscillator hit danger zone levels, the risk has been too high and the reward too low for Cramer to buy stocks.
"While I have tremendous conviction that the inputs are positive, which would mean you should be buying high quality stocks that you think are undervalued, my discipline nevertheless says hold off, because a better, lower level is coming," Cramer said. (Tweet this)
It is official, until this market goes lower or works off its oversold condition — Cramer is staying on the sidelines. Maybe he will take some profits for his charitable trust, but until that oscillator drops back to lower levels, he won't be pressing the buy, buy, buy button on his for a while.