The stock market has had a huge run since it bottomed seven years ago, and many investors have made a significant amount of money if they invested in that generational low.
So, is there a bubble?
When Cramer looked at New York City real estate, it certainly felt like a bubble to him. This was particularly evident in Manhattan, where properties can easily sell for four or five times more than they would go for outside of the city.
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Historically, interest rates are also much lower than where most expected them to be. Many Federal Reserve members are concerned about the bubble Trump mentioned. But, Trump pointed out that these rates aren't available to most people, unless they are rich. And while credit has loosened lately, Cramer found that judgment to be correct.
Trump also noted that the strong dollar is hurting stock investments. Again, Cramer agreed, but that doesn't mean he thinks Trump should be investing in stocks.
"If the reports of Donald Trump's wealth are true, and I have no reason to doubt them, then he shouldn't even be in stocks at all, except for, perhaps some fun," Cramer said.
One of the most memorable lessons Cramer learned working at Goldman Sachs is that an investor only needs to get rich once. There is no point to taking the risk of owning stocks to make more money when you're already filthy rich. Those investors tend to buy bonds.
Every day, hot stocks soar and then crash back down a few weeks or months later.
"In that sense, I think Trump is right, stocks do have tremendous risk. I never want to minimize that risk," Cramer said.
For the vast majority of Americans, who are not rich and are unlikely to get rich from their jobs, Cramer recommended that investors, after putting away nest egg money, try to find stocks that have the capability to deliver outsized gains.
Ultimately, Cramer thinks Trump and many other individuals need to be careful about being too negative, given that there aren't many other options outside of stocks that offer the ability to make a lot of money in this economy.
"That is why I believe that, as long as you take a long-term view, put money away in an index fund, and then set some savings aside for smart, homework-derived investment ideas based on companies you know and love, it's worth braving all the bubble talk to invest in the stock market," Cramer said.
There will always be bubbles, Cramer added, and there will be times when stocks are stretched. But stocks still represent a better value for the average person. And that is why he says not to let the bubble-heads scare you away.