Freedom and Duty seem to be huge components in Kiki's Delivery Service. The name of the dirigible is "The Spirit of Freedom." Kiki has an unusually heavy duty to fill at such a young age and seems to suffer and grow a lot because of it.
I think freedom versus duty plays a large roll in most people's coming of age. There is that free spirit, and there's also the reality of being a slave to our circumstances. When Kiki delivers that herring pie to the ungrateful granddaughter I think a lot is being said here. Surely the granddaughter is being honest and free when she reveals that she doesn't like these stupid presents her grandmother sends her, but she's also being selfish. How much is selfishness a component of freedom? But then, how much is duty a component to embracing what we as humans need as social animals? We need healthy relationships with family, friends, and our place in society which can appear frighteningly claustrophobic to the free spirit. We kind of hate the granddaughter's audacity to freely state how she truly feels about Grandmother's pies, because she lacks the maturity to see the bigger picture, and what it meant as a Grandmother's duty to bake for her birthday.
Kiki is alienated from other kids her age and seems to bond better with adults in the film. Kiki's suffering and alienation seems to come from not being able to fit in with the more free-spirited adolescents. Or of being jealous with their being able to be more free; Kiki is after all being asked to grow up faster than them, but not without a sense of loss. Tombo and Ungrateful-Granddaughter are off to explore the Spirit of Freedom together when Kiki is at her lowest and most alienated. Tombo invites her to come with them, of course, but doesn't understand why she turns moody and rejects the invitation.
Kiki's duty might be delivery incidentally, but overall her duty is to be the sole witch of the city she's chosen. In her struggles, though, she loses the innate gift that allows her to perform her duty. She loses confidence, certainly. But she seems to lose the will to carry on the rest of her life under the weight of her duty.
But she regains her will and ability by achieving something important for someone she cares about and doing it visibly to the benefit of the entire society. She rescues Tombo from the Spirit of Freedom gone awry. This, to me, shows that the sometimes unbearable weight of duty upon our shoulders is lightened and made grand for what we ultimately get out of it by finding our place within society, and forming relationships that are more important than our own ego... which is ultimately more rewarding than being completely free.
In an interesting East vs. West comparison, I find it so interesting how duty is seen as a huge virtue in the East but 'duty' is almost a bad word in America, Land of the Free. Americans hate to admit to themselves that they aren't free. Rugged individualism and freedom are the values America was founded upon, and the values that made America so great, or so the average American is inclined to think. But perhaps Kiki's delivery service reveals something to us in America about duty in such a subtle way that we don't even notice it. Americans aren't free from the laws of nature and society... we in fact do do our duty whether we want to admit it or not. Duty might even be a secret core value we just have an awkward relationship with it.
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I'm actually quite amazed at how rich Kiki's Delivery Service has turned out to be. When I first saw this film I thought it was one of the more simple Miyazaki films thematically. But once you start to look at it, it becomes very richly layered and complex. It's a coming of age story. It explores duty versus freedom, and talent versus becoming jaded. It explores magic versus technology, as well as their peaceful coexistence. The radio and TV are pieces of technology that express music and animation which are art, and art may be one of the last refuges for magic in the modern world. In the epilogue, Kiki is flying magically next to Tombo flying with technology. Kiki's the music and Tombo's the radio.
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Jiji's existence reminded me a lot of a formula used frequently in Disney films. That is of the main protagonist having one or more cute anthropomorphic animal sidekicks that offer a lot of amusement and comedy. But this anthropomorphic Jiji does something that Disney would probably be loathe to do: he's dead by the end of the film. In fact, Disney was undeniably loathe to do it in that they changed this in their dub of the film! Jiji is no longer an anthropomorphic best friend, but rather a pet.. Which actually seems like a great way of showing Kiki's growth. It's kind of bittersweet because it's her immaturity that has died but she's found meaningful best friends in Ursula and Tombo instead. Jiji is her inner child, gone but still there in a in a changed form by the end.