It may seem hard to believe, but stocks of great companies get cheaper when their share prices go lower, Jim Cramer reminded his Mad Money viewers Tuesday. It turns out, the old adage of buy low and sell high is still a solid investment strategy.

This notion seems lost on many investors, however. Cramer said most investors run away from stocks in decline and not toward them. Case in point: Apple (AAPL) - Get Apple Inc. (AAPL) Report , a stock that had fallen from $131 to just $92 in 2016, before rallying to just over $160 a share today. The same is true for Caterpillar (CAT) - Get Caterpillar Inc. Report , which has seen its shares rise 50% over the past 12 months.

From today's Apple product event: Here Is Why Apple's New iPhone X Might Ignite a $2 Trillion Boom

Many investors are fretting over the price United Technologies undefined is proposing for Rockwell Collins (COL) , ignoring all of the money the company has made investors after its last seemingly overpriced acquisition.

Then there's the story of Marriott Vacations Worldwide (VAC) - Get Marriott Vacations Worldwide Corporation Report , which saw its share fall from $91 into the $50s on fears Airbnb was eating into the company's market share. Turns out those fears were not warranted and shares have since doubled.

So the next time your favorite stock heads lower, Cramer said, you should see it as an opportunity, because it probably is.

Time to Get Real 

Is tax reform really going to happen? Cramer said American companies could surely benefit from the repatriation of overseas assets and lower tax rates, but after the debacles over healthcare and a border tax, he's not hopeful that Congress can get anything done.

Cramer called himself a realist, saying that after wasting precious time and momentum debating healthcare reforms, Congress doesn't seem to have learned the lesson that the key to getting things done is to keep things simple.

The same applies to infrastructure. Cramer said Congress could just issue savings bonds to pay for these much-needed projects. Americans would buy them, he said, because we're patriotic. But instead, the wrangling begins again as alternative funding sources are being discussed that are far more complicated and controversial.

The best is the enemy of the good, Cramer concluded, which is why he's hopeful for progress, but certainly not counting on it. 

On Real Money, Cramer says get over it: Infrastructure and tax reform aren't happening this year. Invest in what is growing. Get Cramer's insights with a free trial subscription to Real Money.

Off the Charts: Oil Refiners

In the "Off The Charts" segment, Cramer checked in with colleague Bob Lang over the charts of the oil refiners, the industry most likely to profit from the shutdowns caused by hurricane Harvey in Texas.

While it may seem counter-intuitive that refiners would profit from the shutting down of refineries, Cramer explained that not all refiners were affected by the storm, and the 3-2-1 Crack Spread, the number you get from subtracting the cost of three barrels of oil from two barrels of gasoline and one barrel of fuel oil, shows that those who did remain online, will make a killing.

Lang noted that Andeavor (ANDV) has been steadily heading higher since April and is now completing a bullish flag pattern. Valero (VLO) - Get Valero Energy Corporation Report meanwhile, has also been able to rally despite having to shutdown five of its refineries.

Finally, Lang noted that Holly Frontier (HFC) - Get HollyFrontier Corporation (HFC) Report has been on fire, up 40% since early June.

Cramer said that the fundamentals support Lang's technical analysis and all of these names are likely to head still higher.

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For more detailed analysis and all the charts on these companies, see Oil Refiners Are Rebounding: Cramer's 'Off the Charts'.

Executive Decision: Ventas

For his "Executive Decision" segment, Cramer again spoke with Debra Cafaro, chairman and CEO of Ventas Inc. (VTR) - Get Ventas, Inc. Report , the medical REIT with shares that are flat over the past 12 months as investors have become concerned with the company's senior living properties.

Cafaro said she's most excited about her company's $2 billion investment into university-centered research facilities. She said these facilities will become hubs of research and innovation and over 75% of their partners are A-rated, mitigating credit risk.

But beyond these facilities, Cafaro noted that Ventas has always believed in financial strength and flexibility. She addressed concerned about their senior living business by saying that in some markets, there is a mismatch between the number of facilities available and the immediate demand. But this is part of the normal cycle, and that demand will be absorbed quickly. There were twice as many new facilities being build two years ago compared to today, a positive sign that the correction is already underway.

Finally, Cafaro commended the staff at their 10 facilities that were evacuated during the recent hurricanes. She said despite having the monumental task of evacuating frail seniors, their operators did a remarkable job at keeping everyone safe.

Cramer and the AAP team are adding to their position in Nucor Corp. (NUE) - Get Nucor Corporation Report . Find out what they're telling their investment club members and get in on the conversation with a free trial subscription to Action Alerts PLUS.

Executive Decision: New Relic

For another "Executive Decision" segment, Cramer again welcomed Lew Cirne, CEO of New Relic Inc.  (NEWR) - Get New Relic, Inc. Report , to the show for an update. Shares of New Relic have been on fire in 2017, up over 75%.

Cirne explained that New Relic makes the tools that professionals use to keep their web properties up and running, because downtime in today's world can cause irreparable damage to a company's brand. For companies like, now part of Walmart (WMT) - Get Walmart Inc. Report , as well as Major League Baseball, New Relic offers realtime insights into exactly what's going on within a network, what customers are doing and what their experience looks like.

Cirne said that while New Relic competes against companies like Cisco Systems (CSCO) - Get Cisco Systems, Inc. Report , only New Relic is 100% cloud based and that's where more and more companies are headed with their IT infrastructure.

Cramer said that New Relic's stock has been a rocket because their business has been a rocket.

Lightning Round

In the Lightning Round, Cramer was bullish on RH (RH) - Get RH (Restoration Hardware) Report , Walt Disney (DIS) - Get Walt Disney Company Report , Wynn Resorts (WYNN) - Get Wynn Resorts, Limited (WYNN) Report , NVIDIA (NVDA) - Get NVIDIA Corporation Report and Freeport-McMoRan (FCX) - Get Freeport-McMoRan, Inc. (FCX) Report .

Cramer was bearish on Advanced Micro Devices (AMD) - Get Advanced Micro Devices, Inc. Report and Under Armour (UAA) - Get Under Armour, Inc. Class A Report .

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At the time of publication, Cramer's Action Alerts PLUS had a position in NUE, AAPL, NVDA.