It's easy to spread fear, but it's much harder to stay calm and carry on, Jim Cramer told his Mad Money viewers Thursday. After today's market rebound, Cramer said it's clear that those investors who panicked and sold into the market's plunge earlier this week were dead wrong.

Cramer explained that there are many reasons not to sell into a panic, not the least of which is when everyone is bearish, there's no one left to sell, which often leads to a quick reversal. So why did the bears get it wrong? Cramer gave five reasons.

First, he said that the bears misread low interest rates as bad news and that the economy is doing poorly. In reality, much of our economy does better with lowers rates. Second was the devaluation of the yuan. Here again, Cramer saw positives, as it means U.S. consumers won't have to eat all of the tariffs. The third thing the bears got wrong was the U.S. labeling China as a currency manipulator. Cramer said this was merely a symbolic move and everyone always knew how China manages its currency.

Lastly, Cramer called out the strong and stronger earnings as two other things the bears got wrong. There were more winners this earnings season and more companies benefiting from a strong dollar.

Investors who panicked earlier this week and sold everything missed out on big gains like Advanced Micro Devices (AMD - Get Report) and Booking.com (BKNG - Get Report) , and especially Roku (ROKU - Get Report) , which shot up over 20% Thursday as business was far better than expected. 

Cramer and the AAP team say this week proves dips can be bought. 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.

Opportunities in Healthcare

Don't let fear blind you to opportunities, Cramer reminded viewers. In addition to this week's market plunge, we also saw two great new IPOs that got lost in the panic.

Cramer said diabetes monitoring company Livongo Health (LVGO) may be a long way away from profits, but the company's technology is terrific and its services are accepted by four of the seven top insurance providers. Shares opened at $28 and spiked to $40 before the market meltdown, and at nine times sales, Cramer said, they're a bargain as long as you buy in stages on weakness.

Cramer was also bullish on Health Catalyst (HCAT) , a healthcare data and analytics provider with shares that debuted at $26 and rose to $46 at their peak. This stock trades at just six times sales, and Cramer said given the company's growth rate, that's a very reasonable valuation. 

Executive Decision: Pet IQ

For his "Executive Decision" segment, Cramer spoke with Cord Christensen, chairman and CEO of PetIQ (PETQ - Get Report) , the pet health provider that just posted a 35-cents-a-share earnings beat.

Christensen said they continue to expand their partnerships with major retailers and they also continue to grow their commerce business, which rose 402% in 2018. He explained that PetIQ's mantra is to "follow the pets," and since most pet food comes from large retailers, that's the best place for PetIQ clinics. Most pets still don't receive adequate healthcare, Christensen said, and PetIQ is trying to change that.

When asked about competition from Chewy (CHWY) , another big name in the pet care space, Christensen said that the two companies are aligned in their mission and work together.

Finally, when asked for an update on their Perrigo (PRGO - Get Report) animal health acquisition, Christensen said the $185 million deal is going well and is exactly as they expected. 

Executive Decision: Five9

In his second "Executive Decision" segment, Cramer sat down with Rowan Trollope, CEO of Five9 (FIVN - Get Report) , the call center software provider with shares that popped 6.8% after the company reported strong earnings.

Trollope said Five9 is helping companies replace legacy call center systems with intelligent, modern ones that both they and their customers will love. Their systems help route customers to the right person quickly, ensuring the best possible outcomes.

The power of Five9 comes from its omnichannel approach, Trollope added. Their system can combine everything a company knows about you and use all of that information to not only direct you to the best agent, but also make sure the agent has everything they need to answer your question.

Five9 counts global brands like Estee Lauder (EL - Get Report) as customers, as well as essential services like Expedia (EXPE - Get Report) . Shares of Five9 are up 18% in just the past month.

What Happened to BRIC?

In his "No-Huddle Offense" segment, Cramer asked viewers, "whatever happened to BRIC?" The term, coined in 2001, stood for the high-growth countries of Brazil, Russia, India and China, and they were the place to be if you wanted to make money. Or so we thought.

One by one, the BRIC countries became hazardous to your portfolio. Brazil entered a perpetual recession, while Russia became a nightmare for businesses not affiliated or owned by Vladimir Putin. India was thought to be a road to riches, but so far, no American company has been able to crack the code to making money.

Then there's China, which had been gold for many U.S. companies, until President Trump's tariffs. Now, if your company does business in China, your stock is despised, Cramer said. 

Lightning Round

In the Lightning Round, Cramer was bullish on Twitter (TWTR - Get Report) and Innovative Industrial Properties (IIPR - Get Report) .

Cramer was bearish on MPLX (MPLX - Get Report) , Cloudera (CLDR - Get Report) and Carrizo Oil & Gas (CRZO - Get Report) .

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At the time of publication, Cramer's Action Alerts PLUS had no position in the stocks mentioned.