Mrs. Frisby and the Rats of NIMH

Fiction | Novel | Middle Grade | Published in 1971

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Summary

Chapter Summaries & Analyses

Chapters 1-8

Chapters 9-18

Chapters 19-Epilogue

Character Analysis

Themes

Symbols & Motifs

Important Quotes

Essay Topics

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Discussion Questions

Themes

The Double-Edged Sword of Knowledge and Technology

Knowledge is a powerful tool for freedom and independence, but balance is critical to avoid what Nicodemus sees as an inevitable end to the colony should they continue on the same path. In Mrs. Frisby and the Rats of NIMH, knowledge propels the rats to freedom, but it is also the reason they are trapped to begin with. Humans captured the rats with the goal of scientific discovery, and in doing so disregard the lives of the animals they were experimenting with. When Robert C. O’Brien wrote his novel, he was inspired by a real-world experiment conducted by scientist John B. Calhoun, who placed hundreds of rats into what he called a rat utopia. Overcrowding and psychological stress led to a complete collapse of the rat communities in Calhoun’s experiment, and some of the concerns with the outcome of these real-world experiments are reflected in the fictional world of the rats of NIMH.

Knowledge allows the rats to escape NIMH and develop their own civilization underneath the rosebush using electricity, running water, and other technologies. It also eventually allows them to create plows and learn how to agriculturalize their environment to become fully independent from humans. However, this knowledge also creates a point of no return for the rats, who can now never go back to being regular rats. Not only would the rats not wish to return to what would likely be a sad existence because they have known what it’s like to have a much stronger understanding of the world, but also the regular rats would likely not welcome them back since they would be strange and deeply misunderstood in a regular rat colony.

The pitfalls of technology are illustrated in the novel with Nicodemus’s story about the vacuum cleaner and the need for the growing rat colony to steal from the humans to survive. The woman in the story initially saves herself some time and labor with new technology, but eventually the need for the electricity to run the new technology that has now been adopted by everyone else is eating up the time and labor she saved because the soot has made things even dirtier. Likewise, the rats are learning more and more and raising a new generation who don’t even know what it was like without the knowledge and the luxuries it brings, which is certainly a boon for ratkind. However, they are still stealing the electricity, food, and supplies from the farmer because they are not yet self-sufficient. Should the farmer move or die, the rats will be left without sources of sustenance and the ability to maintain their current quality of life. Therefore, despite their development, they really are no better off than they were as regular rats, just like the woman is no better off with her fancy new vacuum. Nicodemus understands the double-edged nature of their situation and continues to push for the colony to eliminate the inevitability of their future by moving to Thorn Valley.

Literacy as Power

Though the rats are all very intelligent, their intelligence does them no good at the beginning of their time in the lab. It isn’t until the scientists decide to teach the rats how to read that the rats have a chance to escape their imprisonment. Once Justin is able to read the instructions on how to unlock his cage, he can begin his search for an escape. Once that escape is successful, the rats are free but still vulnerable and a bit confused about where they should go and what they should do with themselves since they can no longer satisfactorily live the life of an ordinary rat. Once they stumble on the well-stocked library at the Boniface Estate, they are all able to learn trades and begin to understand the world around them. Without this understanding, the rats would have continued on without ever advancing their civilization, which would have been just as tragic a fate as if they had remained in the lab and continued to run through the mazes with no real destination.

With the power of literacy, the rats can learn anything, and therefore they can become anything. Though Nicodemus feels strongly that stealing their sustenance from the humans is condemning the colony to continue to run the Rat Race, without being literate he would have no way to actually solve this problem even with the intelligence to ponder it. Since he and the other rats are literate, however, they all have the ability to formulate, organize, and execute their Plan. Nicodemus also plans to write a book telling their story one day, which will build the foundation of a written history for future generations.

The rats, Jonathan Frisby, and Mr. Ages are all very aware that being literate is the key to unlocking the full potential of their intelligence. Jonathan teaches all his children, who are his genetic legacy and have each inherited some level of his unnatural intelligence, to read, and he even teaches his wife, who while quite clever is still just a regular field mouse, since he knows how much it can enhance her life even if she never becomes as good at it as the children. Isabella—just a child rat by Mrs. Frisby’s estimation—is startled by Mrs. Frisby in the library, tosses her papers everywhere, and complains that she was supposed to be practicing her reading. This demonstrates the rats’ understanding of how critical reading is to the growth of their society and that reading is likely a compulsory part of a young rat’s education. Through the rats’ understanding of how critical literacy is O’Brien demonstrates how critical literacy is to human life as well and how important it is to be able to lead a full life as a responsible and productive member of society.

The Meaning of Home

One of the central themes of Mrs. Frisby and the Rats of NIMH is the idea of home, what a home means, and what defines a home for each of the animals who live on and around the Fitzgibbon farm. The story begins as Mrs. Frisby awakens at her home to the smell of spring in the air. She knows the arrival of spring means Mr. Fitzgibbon will be plowing his garden soon, and the cinder block where her family lives is located there. The family usually moves to the summer brook in the warmer months, but Timothy has fallen ill, and Mrs. Frisby worries if he will heal in time for the move. It is not long after that she finds out she only has five days to move before the plowing begins—much less time than she expected to have. It is with the help of the rats that she and her family are able to remain safe in their home.

For Mrs. Frisby, home means family and comfort. A home for her is wherever her children are, and for this winter that happens to be the cinder block. The cinder block is perfect for her family and “lay on its side in such a way that the solid parts of the block formed a roof and floor, both waterproof, and the follows made two spacious rooms” (2). The Frisbys have a bedroom that they all share, and a living room to spend time in during the day. The family spends most of their time together, talking, learning, eating, and sleeping. They are extremely close, and care deeply for one another. Their home is underground, out of sight of the farmer and predators, and thus for the Frisbys home also means safety.

The rats also share a place in illustrating the meaning of home within the story. Originally, the rats’ home was in a marketplace they regularly scavenge at night. It is a normal rat’s life, but a good life, until they are captured by scientists and taken to a laboratory. The rats become super intelligent and develop extended life, and eventually learn to escape the laboratory. None of the rats ever considered the lab their home despite living there for several months. After escaping, they struggle to establish a true, settled home. They drift from place to place, stealing what they can, until they finally settle on the rosebush. However, the life they build there does not provide them the comfort a home is meant to, and they become dissatisfied with how easy it has become. The rats strive to create a true home by moving to Thorn Valley and putting an end to their stealing and reliance on humans. The plan is to stay forever, and there is “no talk of their coming back” (226).

Adapting in the Face of Forces More Powerful Than Oneself

The animals in Mrs. Frisby and the Rats of NIMH have to adapt to outside forces that are beyond their control and much more powerful than themselves. These forces include the natural elements, such as weather and disease; the constant struggle for food; the avoidance of predators like Dragon; and most of all, the humans. The mice and rats are small, and the world around them is massive. They must learn to survive and thrive despite these disadvantages, and they manage to do just that.

When the rats lived in the laboratory, they were at the mercy of their handlers. They lived in cages, were fed pellets, and experimented on daily. When the rats are captured, there is nothing they can do; they are surrounded by the humans and taken. Nicodemus explains that “the uncertainty itself was the worst suffering [they] had to undergo” (105)—never knowing what would happen, why they were there, or whether they would ever escape. The rats learned to adapt in this environment by observing the scientists, so they knew what was coming as well as when they were free to talk among themselves and eventually start coming out of their cages when the scientists weren’t around. They also learned to clean up after themselves to cover their movements. In other words, they learned how to manipulate the scientists until they could finally escape for good. These skills also come in handy at the Boniface Estate, the toy tinker’s truck, and at the Fitzgibbon farm, as they needed to keep knowledge of their presence to a minimum.

Mrs. Frisby lives a similar existence, never knowing whether she or her children will survive another day or another year. Since her husband died, she fears the same fate will befall her or one of her children. Timothy is sick often, leaving the family prone to disease and death, and Mrs. Frisby must regularly risk her life searching the farm for food. In fact, Mrs. Frisby has to plan her every step carefully, skillfully avoiding detection: “she chose her path where the earth was bare, or where grass grew, and she avoided dead leaves, which would rustle and crackle even under her small weight” (11). With the help of the rats and their knowledge of physics and engineering, Mrs. Frisby and her family are finally able to live in peace and safety after the move.

Rats and mice are considered of lower class both in the animal world and in the eyes of humans. Nicodemus points out that rats are possibly the most despised creature, and although he knows rats can sometimes carry diseases, he knows humans carry far more. Furthermore, rats and mice are prey to many other animals like cats, owls, and snakes. Nicodemus and the other rats become super intelligent and are taught to read, and through their newfound knowledge they attempt to rise above their position in society. Nicodemus knows how dangerous it is to be dependent on creatures more powerful than themselves: “We’re just living on the edge of someone else’s [civilization], like fleas on a dog’s back. If the dog drowns, the fleas drown, too” (173). For this reason, Nicodemus and the other rats decide to leave the farm and create their own independent society, free of dependency on humans.