1. Mariela Chaves Fernández Clever Hans English III ULACIT

2. WasanOrlovTrotterhorsethatwasclaimedtohavebeenabletoperformarithmetic and otherintellectualtasks.

3. After a formal investigation in 1907, psychologistOskarPfungstdemonstratedthatthehorsewasnotactuallyperformingthese mental tasks, butwaswatchingthereaction of hishumanobservers. Oskardiscoveredthisartifact in theresearchmethodology, whereinthehorsewasrespondingdirectlytoinvoluntarycues in thebodylanguage of thehumantrainer, whohadthefacultiestosolveeachproblem. Thetrainerwasentirelyunawarethat he wasprovidingsuchcues

4. In honour of Pfungst'sstudy, theanomalousartifact has sincebeenreferredto as theClever Hans effect and has continuedtobeimportantknowledge in theobserver-expectancyeffect and laterstudies in animal cognition.

5. Thepublicwasespeciallyinterested in animal intelligencedue in a largepartto Charles Darwin’sthenrecentpublications. Spectacle XX CENTURY

6. Hans was a horseownedbyWilhelm von Osten, whowas a gymnasiummathematicsteacher, an amateur horsetrainer, phrenologist, and something of a mystic. Hans wassaidtohavebeentaughttoadd, subtract, multiply, divide, workwithfractions, tell time, keeptrack of the calendar, differentiate musical tones, and read, spell, and understandGerman

7. Ostenwouldask Hans, "Iftheeighthday of themonth comes on a Tuesday, whatisthe date of thefollowing Friday?”. And Hans wouldanswerbytappinghishoof.

8. Questionscouldbeaskedbothorally, and in writtenform. Hans'sabilitiesappearedon page six of The New York Times.

9. Aftervon Ostendied in 1909, Hans wasacquiredbyseveralowners. Itisbelievedthatthehorsewasputto use in somecapacity in WorldWar I. After 1916, thereis no record of him and hisfateremainsunknown