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Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid.” 

~  Albert Einstein is credited with this quote, but the origin is unclear

The Hard Science & The Story Behind the Science

Chaser's learning is hard science, which is why she has attracted so much attention. She has the largest tested vocabulary of any animal in the world. And it is the way she understands that words have independent meaning and can combine them into simple sentences that garners her this title. Her FORMAL language learning even tops that of primates and dolphins and she has been dubbed by the media as "the smartest dog in the world." While this title simplifies her groundbreaking accomplishment in a meaningful way, there is literally no way to measure the intelligence of any animal beautifully demonstrated in the above quote - attributed to Albert Einstein. They all have their own unique genius which we as humans must recognize. Chaser's research strongly indicates that dogs are much smarter than we give them credit for and science is just beginning to catch up.

The goal of this research was to test the boundaries of the canine mind and John Pilley stopped at 1,022 objects simply because he figured it was enough and his wife Sally didn't want any more toys in the house. Chaser has continued to learn new words every day and if it wasn't for Pilley's own advanced age, they could have discovered even more. He never came close to reaching the boundaries of her cognitive capabilities and Chaser's learning has been thus far been limitless. 


The Research team 

John W. Pilley, Chaser & Alliston K. Reid


Behavioural Processes

Volume 86, Issue 2, February 2011, Pages 184-195

Border collie comprehends object names as verbal referents


Learning and Motivation

Volume 44, Issue 4, November 2013, Pages 229-240

Border collie comprehends sentences containing a prepositional object, verb, and direct object

Why did he do it?

In 2004, when Dr. John W. Pilley, Emeritus Professor of Psychology at Wofford College got his two-month-old puppy Chaser as a gift from his wife Sally, he wanted to explore the boundaries of the canine mind and delve deeper into the communication between humans and man’s best friend. He set his eye on teaching Chaser human language and discovered that her capacity to learn was beyond his wildest dreams. She mastered the names of more than a thousand toys which would later be incorporated into sentences with multiple elements of grammar.


But at 80 years of age, John knew that if he had a shot at getting his findings published in a peer-reviewed journal, he would need help. So, he reached out to his long-time friend and esteemed colleague, Dr. Alliston K. Reid. As a Reeves Family Professor of Psychology at Wofford College, Alliston had extensive experience in the world of scientific journalism and accepted this arduous challenge. He knew that John’s data was so groundbreaking that they had to devise a rigorous method for testing Chaser that would hold up to powerful, stringent, peer review. It would not be easy.


But they did it. In late December 2010, their work was published by the Elsevier journal Behavioural Processes, which went globally viral in over 72 languages - taking not only the canine cognition world by storm - but ringing the bell loudly for dog owners all over the world with empirical, scientific, evidence that dogs are not only as smart as we think, but capable of so much more. Since 2011 their story has been featured in hundreds of publications such as TIME, The Wall Street Journal, The New York Times, and Scientific American, and on television programs like 60 Minutes, Nova ScienceNOW, ABC World News, and The Today Show. Pilley also penned a New York Times best-selling book with writer Hilary Hinzmann, “Chaser, Unlocking the Genius of the Dog Who Knows a Thousand Words".

John Pilley continued teaching Chaser extended elements of grammar where words had independent meaning. Her comprehension of sentence structure was published in the Elsevier Journal of Learning and Motivations. 

Both Studies are above.

Why teach words to dogs - what's the big deal? 

We are often asked, “Why teach your dog language?” Scientifically, there are many, many reasons and those who do not believe in the value of teaching animals human language has clearly been unable to do it successfully. Socially speaking, the answer is very simple; communication is key in any relationship. As humans, we rely on thousands of languages daily, be it verbal, visual, or technical, to foster connections, relay information, and express ourselves to others. Communication is a gateway to greater understanding, further discovery, and deeper bonds. And just as with fellow humans, the more you are able to communicate with your dog, the greater your understanding will be, of what your dog is communicating with you.

It is something I have always sought with our family animals.

Border Collie Comprehends over 1000 Object Names as Verbal Referents

Some dogs may understand that our sounds refer to particular objects and not just commands.

Spartanburg, S.C., USA, 6 January, 2010 – Researchers at Wofford College discovered that a Border Collie comprehends the names of over 1000 objects, differentiating between names of objects and orders to fetch them. This research deepens the findings of researchers in Germany, who had discovered a dog that knew the names of a couple of hundred objects. Important questions were left open as to how far a dog could go, and whether the dog really understood that the object names were nouns and not commands to retrieve the object.

John Pilley and Alliston Reid answered two central questions with their research: How large can a dog’s vocabulary become if given extensive training? What do dogs actually understand when we use human language to communicate with them? These findings are published in the Elsevier journal Behavioural Processes.

The authors demonstrated that their dog, Chaser, learned the names of 1022 objects - no upper limit is apparent - they stopped training the dog after three years due to their time constraints, not because the dog could not learn more names. This study demonstrates Chaser’s ability to learn the names of proper nouns, and her extensive vocabulary was tested repeatedly under carefully controlled conditions. The authors admitted that she remembered the names of each of her 1022 toys better than they could. Chaser’s ability to learn and remember more than 1000 proper nouns, each mapped to a unique object, revealed clear evidence of several capacities necessary for learning receptive human language: the ability to discriminate between 1022 different sounds representing names of objects, the ability to discriminate many objects visually, an extensive vocabulary, and a substantial memory system that allowed the mapping of many auditory stimuli to many visual stimuli.

Their second experiment demonstrated that Chaser really understands that these are names, and not commands to fetch the object. In order to test independence of meaning of nouns and commands, the authors randomly combined nouns with commands to see if Chaser would produce the correct behavior toward the correct object in each trial. Without special training, Chaser responded to each combination correctly, even on the first trial, demonstrating that Chaser understood that the commands and proper-noun names had independent meanings. The dog understands that names refer to particular objects, independent of the action requested involving that object.

Their third experiment demonstrated that the dog also understands names for categories of objects or common nouns, and not just individual names or proper nouns. For instance, she learned that name “toy” referred to the 1022 objects she was allowed to play with, each with a proper-noun name. By forming categories represented by common nouns, Chaser mapped one label onto many objects. Chaser also demonstrated that she could map up to three labels onto the same object without error. For example, Chaser knew the proper-noun names of all objects used in the research. Chaser also mapped the common noun "toy" onto these same objects. Her additional success with the two common nouns "ball" and "frisbee" demonstrates that she mapped a third label onto these objects. Her demonstrations of one-to-many and many-to-one noun/object mappings reveal flexibility in the referential nature of words in border collies.

Each of these experiments showed that the dog could learn names using procedures involving associative learning. Their fourth experiment demonstrated that Chaser could also learn names by exclusion - inferred the name of a novel object by exclusion of familiar already-named objects. Retention of these names using this procedure was limited to short periods, however, just as usually observed with children.

According to Alliston Reid, “This research is important because it demonstrates that dogs, like children, can develop extensive vocabularies and understand that certain words represent individual objects and other words represent categories of objects, independent in meaning of what one is asked to do with those objects.”

Additional research is needed to determine whether these impressive language abilities are shared by other breeds of dogs. This work encourages research into how the historical relationships between humans and dogs may have influenced the abilities of dogs to communicate with humans, and whether this influence is unique to dogs.

“Border collie comprehends object names as verbal referents” by John Pilley and Alliston Reid.

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About the authors
John W. Pilley, Ph.D. is a retired professor of psychology at Wofford College in Spartanburg, SC, where this study was completed.

Alliston K. Reid, Ph.D. is Reeves Family Professor of Psychology at Wofford College in Spartanburg, SC, and currently serves as president of the Society for the Quantitative Analyses of Behavior.

About Behavioural Processes
Behavioural Processes is dedicated to the publication of high-quality original research on animal behaviour from any theoretical perspective. It welcomes contributions that consider animal behaviour, from behavioural analytic, cognitive, ethological, ecological and evolutionary points of view. This list is not intended to be exhaustive, and papers that integrate theory and methodology across disciplines are particularly welcome. The quality of research and focus on these aspects are the sole criteria for acceptance. Papers reporting solely on human behaviour may be considered for publication if they relate closely to non-human research within the journal's remit. Authors of papers reporting research on human subjects are invited to contact the editors for advice prior to submission, as they are for papers of all kinds.

Behavioural Processes publishes three categories of paper. First, regular Research Reports present the results of original experiments or outline novel theoretical positions. Second, invited, critical Mini-Reviews are polemical reviews of an area of animal behavioral research accompanied by a number of responses by peers in the area. Though these reviews are invited, prospective authors are encouraged to contact the editors with their ideas for such papers. Third, Rapid Reports are short communications reporting the outcome of a single experiment in no more than 2000 words and a total of two tables or figures.

About Elsevier
Elsevier is a world-leading provider of scientific, technical and medical information products and services. The company works in partnership with the global science and health communities to publish more than 2,000 journals, including The Lancet and Cell, and close to 20,000 book titles, including major reference works from Mosby and Saunders. Elsevier’s online solutions include ScienceDirect, Scopus, Reaxys, ClinicalKey and Mosby’s Suite, which enhance the productivity of science and health professionals, and the SciVal suite and MEDai’s Pinpoint Review, which help research and health care institutions deliver better outcomes more cost-effectively.

A global business headquartered in Amsterdam, Elsevier employs 7,000 people worldwide. The company is part of Reed Elsevier Group plc, a world leading provider of professional information solutions. The group employs more than 30,000 people, including more than 15,000 in North America. Reed Elsevier Group plc is owned equally by two parent companies, Reed Elsevier PLC and Reed Elsevier NV. Their shares are traded on the London, Amsterdam and New York Stock Exchanges using the following ticker symbols: London: REL; Amsterdam: REN; New York: RUK and ENL.

Media Contact
Francesca Webb
+44 1865 843244

photo: sebastien micke


the smartest dog in the world

​Chaser the border collie
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