Thanks to Ivan Pavlov, we’re all familiar with classical conditioning and the Pavlovian response (ring a bell before giving a dog a plate of food enough times, and he'll eventually begin to salivate at the sound of the bell rather than the sight of the meal). But if you want to know more about the man himself, from his side gig selling canine gastric juice to his couch-surfing days, it's time to examine these 12 drool-worthy facts about Ivan Pavlov.

1. A LOT OF WHAT WE THINK WE KNOW ABOUT HIM IS WRONG.

Pavlov’s biographers point out that most people have misconceptions about the Russian physiologist. For example, instead of ringing a bell to train dogs, Pavlov actually used a variety of tools such as a metronome, buzzer, whistle, light, harmonium, and even electric shock. And Pavlov’s concept of the conditioned response is, in reality, not exactly what he pioneered. He discussed the conditional response, but a mistranslation of the original Russian word uslovnyi gave us the phrase conditioned response, which is still used today.

2. HE PLANNED TO BECOME A PRIEST.

Pavlov was born in Ryazan, Russia in 1849. His father was a priest, and Pavlov enrolled in a theological seminary. But after reading the works of Russian physiologist Ivan Sechenov, Pavlov decided to change course. In 1870, he left the seminary and enrolled at what is now known as St. Petersburg University to study natural science, physics, and math.

3. HIS CHEMISTRY PROFESSOR WAS A BIG DEAL.

During Pavlov’s first year of university, one of the classes he took was inorganic chemistry. His professor, Dmitri Mendeleev, was a big deal in the world of science. In 1869, Mendeleev published the first periodic table of elements and is credited as the father of the periodic table. Not too shabby.

4. HIS EARLY WORK DEALT WITH PANCREATIC NERVES AND ANIMAL DIGESTION.

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Throughout the 1870s and early 1880s, Pavlov studied the natural sciences and physiology, conducting research and working on his doctorate thesis. Specifically, he wrote about the function of the nerves in the pancreas and the heart. In 1890, Pavlov was asked to develop and direct a physiology department at the Institute of Experimental Medicine, where he studied the interplay between the nervous system and digestion.

5. HE WAS SO POOR THAT HE COUCH-SURFED FOR A FEW MONTHS.

Russian scientists worked in modest labs and were paid very little, so Pavlov struggled with finances. In 1887 he couldn’t afford his apartment anymore, so he spent a few months away from his wife Serafima (or Seraphima) Karchevskaya and young son. Pavlov crashed with friends or slept in his lab, and he took on extra jobs; he taught physiology and worked on a medical journal to earn more money.

6. HE FINANCED HIS LAB BY SELLING CANINE GASTRIC JUICE AS A CURE FOR INDIGESTION.

Pavlov kept his physiology lab running by selling something that he had easy access to: canine gastric juice. While conducting experiments on dogs’ digestive systems, Pavlov collected gastric juice from hungry dogs that stared at a big bowl of meat all day. Pavlov paid an assistant to run the gastric juice collection operation, and he sold thousands of containers of the juice each year to people around Europe, who drank it daily to treat dyspepsia (indigestion). Yum!

7. AFTER HIS FIRST SON DIED, HE NAMED ALL HIS FUTURE CHILDREN WITH “V” NAMES.

If you think Pavlov and the Kardashians have nothing in common, think again. After the sudden death of their first child, Wirchik, at a very young age, the Pavlovs had four more children: three sons and a daughter, whom they named Vladimir, Victor, Vsevolod, and Vera.

8. HE WON A NOBEL PRIZE FOR REMOVING DOGS’ ESOPHAGI.

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Although Pavlov’s best-known work—showing how an environmental stimulus can influence a behavioral response—was groundbreaking, he won a Nobel Prize in 1904 for something different. He earned the honor for his research into the animal digestive system. After surgically removing a dog’s esophagus, Pavlov fed the animal and observed how the process of digestion worked, measuring the digestive secretions of the stomach and pancreas.

9. H.G. WELLS WROTE ABOUT PAVLOV FOR THE NEW YORK TIMES MAGAZINE.

In November 1927, science fiction writer H.G. Wells wrote an essay about Pavlov for The New York Times Magazine. Because Wells didn’t fully understand the science behind one of Pavlov’s articles about reflexes, he ignored the heavy-duty science and focused on Pavlov the man. Wells wrote about Pavlov’s "vastly heroic" nature and devotion to advancing science in the face of poverty, war, and revolution. After a 23-year-old B.F. Skinner read Wells’s article on Pavlov, he became a fan and grew up to be one of history’s most influential behavioral psychologists.

10. HE HAD A BAD TEMPER.

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According to his biographer, Daniel Todes, Pavlov had issues with anger management. Beginning in childhood, his mood could change suddenly, and as an adult, he hit aggressive dogs in his lab and was known for his uncontrollable outbursts of anger. Pavlov himself described his angry outbursts as “morbid, spontaneous paroxysms.”

11. HE SPOKE OUT AGAINST SOVIET COMMUNISM.

In 1921, Vladimir Lenin publicly praised Pavlov for his scientific contributions, and the Soviet government funded his research and offered him increased food rations (he didn’t accept). But Pavlov spoke out against communism, requesting in 1922 that he be allowed to move his lab to another country. Lenin refused. Pavlov said, “For the kind of social experiment that you are making, I would not sacrifice a frog’s hind legs!” Pavlov also decried his government’s persecution of political dissidents and clergymen; in a letter, Pavlov told Joseph Stalin that he was "ashamed to be called a Russian." Pavlov wasn’t killed for his contrarian views because the government determined that his scientific work was too valuable for Russia.

12. HIS HOME AND APARTMENT WERE CONVERTED TO MEMORIAL MUSEUMS.

Pavlov’s estate in Ryazan, Russia is now a museum where visitors can explore his life and achievements. If you visit, be prepared to see stuffed dogs (and even a monkey) that Pavlov used in his experiments. And if you find yourself in St. Petersburg, you can check out The Pavlov Memorial Museum, where Pavlov lived for almost two decades before he died on February 27, 1936.