Remember the myth of Pygmalion? He was a sculptor and a prince of Cyprus and he wanted to create an ivory statue of the ideal woman. His efforts yielded a statue, which he named Galatea—and the statue was so exquisite that Pygmalion fell helplessly in love with his own creation. He prayed so fervently to the goddess of love, Venus, to bring Galatea to life that his prayer was answered and he and his lovely wife lived happily ever after. If you roll your eyeballs and sigh with exasperation when you hear things like “If you think positive thoughts, good things will happen,” you may be quite surprised to know that there’s actually scientific proof of the correlation between how our attitudes impact the events of our lives. And the scientific exploration of this seemingly un-measurable metric all began 100 years ago with a horse named Clever Hans.

In 1904, two researchers (with the tongue-defying names of Stumpt and Pfungst) began an investigation of a stallion named Clever Hans who was renowned the world over as an equine mathematical genius. Russian aristocrat Willhelm Von-Osten had single-mindedly set about teaching Clever Hans as though it were a human. By using an abacus and blackboard, he schooled the horse in basic arithmetic, rewarding Hans with carrot bits when answers were correct. Two years of single-minded perseverance were richly rewarded: Clever Hans could add, subtract, multiply and divide by tapping out the solutions with his hoof. Though many other animals had been trained to perform such tricks before, Hans was unique in his ability to run through his repertoire even when Von-Osten was not present. What was going on? Stumpt and Pfungst were determined to crack the mystery. Well it turns out that Clever Hans was a very clever horse—just not in the way Von-Osten imagined. For starters, if the horse could not see the questioner, Hans was not clever at all, tapping his hoof randomly and supplying incorrect answers. Similarly, if the questioner did not himself know the answer to the question, Hans could not answer either. Now the researchers got really curious. What cues was Hans using? They must be incredibly subtle since so far noone had picked up on Han’s tricks. After more intense scrutiny Stumpt and Pfungst noticed that a forward inclination of the questioner’s head would start Hans tapping. And as the questioner straightened up, the horse would stop. In fact, Hans was so incredibly tuned in to minute changes in the questioner that an arch of the eyebrow could stop the tapping hoof, or even the slight flaring of the questioner’s nostril! In other words, unwittingly, people were giving the horse the correct answers by communicating their expectations to him via physical signals. Hans’ brilliance lay in his ability to pick up on those signals—even signals that were absolutely unconsciously given and indiscernible to all but the most inquisitive eye. Hans, the brilliant mathematical stallion was only clever when people expected him to be! He delivered to their expectations—no more and no less.

The notion of the self-fulfilling prophecy (also known as the Pygmalion Effect)  is widely taught in management and education circles. It says that once an expectation is set, even it isn’t accurate, we tend to act in ways that are consistent with that expectation. The self-fulfilling prophecy is a persistently held belief in another person such that the belief becomes a reality. The person believed in, being believed, becomes the person whom they are perceived to be. When we look at our own lives, at an instinctive level, we know the self-fulfilling prophecy to be true. As parents, we know the impact our beliefs have on our children: tell them a challenge is too great, and you can be sure that most kids will crumple under the pressure of a stretch well within their reach; share with your kids how bright and capable you know them to be, and watch them operate in the world as bright and capable people. Scientific studies have shown that if you tell a grammar school classroom teacher that a child is bright, the teacher will be more supportive, teach more difficult material, allow more time to answer questions, and provide more feedback to that child. The child receiving this attention and basking in the teacher's belief learns more and is better in school. It does not matter if the child is actually bright. All that matters is that the teacher believes in the child. In our professional environments the Pygmalion Effect holds true as well. Managers and supervisors who truly believe in the high capabilities of their direct reports consistently get better performance. So, if you manage others, set a clear expectation that each employee will make a significant impact on the work group's ability to succeed. Ensure that your employees have a clear understanding that there is no question of them performing well—and they will strive to meet your expectations of them. Consciously or not we tip people off as to what our expectations are. We exhibit thousands of cues from the language we use to the body language we communicate with. If expectations can create reality, there is an enormous incentive to have high expectations of the people in our spheres of influence. So take a mental scan of the people whose lives are truly impacted by your beliefs, and confirm that you are communicating in a manner that will enable them to be their best.