The 100th Monkey

A story about social change.

By Ken Keyes Jr.

The Japanese monkey, Macaca Fuscata, had been observed in the wild for a period of over 30 years.

In 1952, on the island of Koshima, scientists were providing monkeys with sweet potatoes dropped in the sand. The monkey liked the taste of the raw sweet potatoes, but they found the dirt unpleasant.

An 18-month-old female named Imo found she could solve the problem by washing the potatoes in a nearby stream. She taught this trick to her mother. Her playmates also learned this new way and they taught their mothers too.

This cultural innovation was gradually picked up by various monkeys before the eyes of the scientists. Between 1952 and 1958 all the young monkeys learned to wash the sandy sweet potatoes to make them more palatable. Only the adults who imitated their children learned this social improvement. Other adults kept eating the dirty sweet potatoes.

Then something startling took place. In the autumn of 1958, a certain number of Koshima monkeys were washing sweet potatoes -- the exact number is not known. Let us suppose that when the sun rose one morning there were 99 monkeys on Koshima Island who had learned to wash their sweet potatoes. Let's further suppose that later that morning, the hundredth monkey learned to wash potatoes.


By that evening almost everyone in the tribe was washing sweet potatoes before eating them. The added energy of this hundredth monkey somehow created an ideological breakthrough!

But notice: A most surprising thing observed by these scientists was that the habit of washing sweet potatoes then jumped over the sea...Colonies of monkeys on other islands and the mainland troop of monkeys at Takasakiyama began washing their sweet potatoes.

Thus, when a certain critical number achieves an awareness, this new awareness may be communicated from mind to mind.

Although the exact number may vary, this Hundredth Monkey Phenomenon means that when only a limited number of people know of a new way, it may remain the conscious property of these people.

But there is a point at which if only one more person tunes-in to a new awareness, a field is strengthened so that this awareness is picked up by almost everyone!

From the book "The Hundredth Monkey" by Ken Keyes, Jr. 
The book is not copyrighted and the material may be reproduced in whole or in part.

Read the whole book.

Please Note:

The 100th Monkey Theory has been on the WOW site since 1996, and we occasionally receive letters claiming that it was a hoax or fake.

We contacted Penny Gillespie, who was married to Ken Keyes and participated in his work and writing. Here is her response:

I'm not sure what you mean by "fake." The Hundredth Monkey is a real book and hundreds of thousands of copies were printed and circulated, often through university courses. People bought them by the case and gave them away.

The story of the hundredth monkey came from a writing by Rupert Sheldrake.

After our book was printed, there was some question about whether the study was authentic. Ken presented the story as a legend, or phenomenon; the concepts of morphogenetic fields and critical mass are very true and the story serves to illustrate them.

Hope that answers your question.

All the best,

Penny Gillespie
President's Club, Platinum Wellness Consultant

We were also forwarded the following article that "puts a new light on this popular story"

The Hundredth Monkey Revisited

by Elaine Myers

Going back to the original sources
puts a new light on this popular story

Is there some magic key that provides a short cut to cultural transformation?

THE STORY OF "The Hundredth Monkey" has recently become popular in our culture as a strategy for social change. Lyall Watson first told it in Lifetide (pp147- 148), but its most widely known version is the opening to the book The Hundredth Monkey, by Ken Keyes. (See below.) The story is based on research with monkeys on a northern Japanese Island, and its central idea is that when enough individuals in a population adopt a new idea or behavior, there occurs an ideological breakthrough that allows this new awareness to be communicated directly from mind to mind without the connection of external experience and then all individuals in the population spontaneously adopt it. "It may be that when enough of us hold something to be true, it becomes true for everyone." (Watson, p148)

I found this to be a very appealing and believable idea. The concept of Jung's collective unconscious, and the biologists' morphogenetic fields (IN CONTEXT #6} offer parallel stories that help strengthen this strand of our imaginations. Archetypes, patterns, or fields that are themselves without mass or energy, could shape the individual manifestations of mass and energy. The more widespread these fields are, the greater their influence on the physical level of reality. We sometimes mention the Hundredth Monkey Phenomenon when we need supporting evidence of the possibility of an optimistic scenario for the future, especially a future based on peace instead of war. If enough of us will just think the right thoughts, then suddenly, almost magically, such ideas will become reality.

However, when I went back to the original research reports cited by Watson, I did not find the same story that he tells. Where he claims to have had to improvise details, the research reports are quite precise, and they do not support the "ideological breakthrough" phenomenon. At first I was disappointed; but as I delved deeper into the research I found a growing appreciation for the lessons the real story of these monkeys has for us. Based on what I have learned from the Japan Monkey Center reports in Primates, vol. 2, vol. 5 and vol. 6, here is how the real story seems to have gone.

Up until 1958, Keyes' description follows the research quite closely, although not all the young monkeys in the troop learned to wash the potatoes. By March, 1958, 15 of the 19 young monkeys (aged two to seven years} and 2 of the 11 adults were washing sweet potatoes. Up to this time, the propagation of the innovative behavior was on an individual basis, along family lines and playmate relationships. Most of the young monkeys began to wash the potatoes when they were one to two and a half years old. Males older than 4 years, who had little contact with the young monkeys, did not acquire the behavior.

By 1959, the sweet potato washing was no longer a new behavior to the group. Monkeys that had acquired the behavior as juveniles were growing up and having their own babies. This new generation of babies learned sweet potato washing behavior through the normal cultural pattern of the young imitating their mothers. By January, 1962, almost all the monkeys in the Koshima troop, excepting those adults born before 1950, were observed to be washing their sweet potatoes. If an individual monkey had not started to wash sweet potatoes by the time he was an adult, he was unlikely to learn it later, regardless of how widespread it became among the younger members of the troop.

In the original reports, there was no mention of the group passing a critical threshold that would impart the idea to the entire troop. The older monkeys remained steadfastly ignorant of the new behavior. Likewise, there was no mention of widespread sweet potato washing in other monkey troops. There was mention of occasional sweet potato washing by individual monkeys in other troops, but I think there are other simpler explanations for such occurrences. If there was an Imo in one troop, there could be other Imo-like monkeys in other troops.

Instead of an example of the spontaneous transmission of ideas, I think the story of the Japanese monkeys is a good example of the propagation of a paradigm shift, as in Thomas Kuhn's The Structure of Scientific Revolutions. The truly innovative points of view tend to come from those on the edge between youth and adulthood. The older generation continues to cling to the world view they grew up with. The new idea does not become universal until the older generation withdraws from power, and a younger generation matures within the new point of view.

It is also an example of the way that simple innovations can lead to extensive cultural change. By using the water in connection with their food, the Koshima monkeys began to exploit the sea as a resource in their environment. Sweet potato washing led to wheat washing, and then to bathing behavior and swimming, and the utilization of sea plants and animals for food. "Therefore, provisioned monkeys suffered changes in their attitude and value system and were given foundations on which pre-cultural phenomena developed." (M Kawai, Primates, Vol 6, #1, 1965).

What does this say about morphogenetic fields, and the collective unconscious? Not very much, but the "ideological breakthrough" idea is not what Sheldrake's theory of morphogenetic fields would predict anyway. That theory would recognize that the behavior of the older monkeys (not washing) also is a well-established pattern. There may well be a "critical mass" required to shift a new behavior from being a fragile personal idiosyncrasy to being a well-established alternative, but creating a new alternative does not automatically displace older alternatives. It just provides more choices. It is possible that the washing alternative established by the monkeys on Koshima Island did create a morphogenetic field that made it easier for monkeys on other islands to "discover" the same technique, but the actual research neither supports nor denies that idea. It remains for other cultural experiments and experiences to illuminate this question.

What the research does suggest, however, is that holding positive ideas (as important a step as this is) is not sufficient by itself to change the world. We still need direct communication between individuals, we need to translate our ideas into action, and we need to recognize the freedom of choice of those who choose alternatives different from our own.


See how the 100th Monkey Theory can work through a new way of thinking called

WOW - Wish Only Well!


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