It’s hard to imagine now, but there was once a time in history when even the most basic form of scientific inquisition was considered an affront to God. Chi: Chikyuu no Undou ni Tsuite (About the Movement of the Earth) is a unique manga penned by Uoto and currently serialized in Weekly Big Comic Spirits that deals with this quandary and more, making for an ambitious project… if one with a few bumps along the way.
Content warning: there are some pretty graphic depictions of torture ahead.
The time is 1500; the setting, somewhere in medieval Europe. Raphau is a child prodigy about to graduate from university with a degree in theology, his future set for him somewhere in the Catholic Church. But then, he comes into contact with a strange man through a chance encounter: branded a heretic, he has an interesting theory about space and the way that the planets move through it.
That’s right: Chi: Chikyuu no Undou ni Tsuite is a manga about the Copernican Revolution, the discovery and development of the heliocentric model, as well as the attempts by powers-that-be to repress it. That’s certainly not a premise I’ve ever seen in a manga before, which was one of the main reasons I got interested in it, alongside its surprise second place in this year’s Manga Taisho awards.
Chi: Chikyuu no Undou ni Tsuite delivers on this premise: not only is it a thoughtful exploration of Renaissance society, it also has several things to tell us today. The one thing holding it back, however, is the quality of Uoto’s art.
The author definitely has some imagination, you have to give him that: volume 1 opens with the grotesque image of a heretic being tortured with a ‘pear of anguish,’ as featured above. This torture device appears in the story and expands when wound, thus rendering the victim unable to speak. Similar moments of brilliance shine throughout the two volumes consulted for this review, but they’re often accompanied by questionable autonomy and poor paneling.
Does that matter, though, when the story being told through the pictures is so captivating and so endlessly thought-provoking? That probably depends on your disposition as a reader, but it didn’t for me.
The Role of Religion in Medieval Europe

Volume 1 of Chi: Chikyuu no Undou ni Tsuite highlights beautifully the role that the Catholic Church played in medieval society, squashing any sort of scientific discovery to preserve the status quo. We see the torture and repression doled out to those that spoke out, while inquisitive minds are advised not to ponder. This was ultimately to defend the divine right of kings and the monarchy, which were attached to the Church by a thousand threads.
Also, the agents of the Church don’t just oppose the heliocentric model for the sake of the story: their reasons are properly explained, allowing us to engage with them on a philosophical level.
The implications of the heliocentric model went against the entire Christian belief system. The assertion that the stars actually revolved around the Earth (the Ptolemaic model) was useful for the Church, as it created a space for Heaven to exist at the top of the universe, with the Earth being located at the bottom. Having the Earth at the center of the universe also symbolized how humans were special, being created in the image of God.
The idea that the Earth actually revolves around the Sun alongside the rest of the planets (which had been around since at least the 4th century BC, by the way) immediately strips our existence of any mysticism, as well as stealing away from God an avenue of existence. Chi: Chikyuu no Undou ni Tsuite is a surprisingly robust exploration of medieval theology, foreshadowing how the slow march of science would eventually eat idealism away to an isolated island.

After a surprise ending to volume 1, volume 2 of Chi. -Chikyuu no Undou ni Tsuite- then moves to focus on a completely different set of characters, exploring a completely different function of religion in medieval society: psychological comfort and a chance at salvation from a short, brutal life.
Okuji and Glas are swords-for-hire, working for feudal lords to settle their disputes and take on duel requests: they’ve seen plenty of death in their time, meaning that they use religion as an emotional crutch. Okuji declares that he has ‘no hope in this world’ and only wishes for a peaceful life after death. Glas, meanwhile, uses the idea of Heaven to reassure himself that he’ll meet his family (struck down by a deadly disease) again some day.
In particular, Glas’ obsession is tracking the movement of Mars: he thinks that this is his family’s way of showing him ‘perfection’ and sending messages from Heaven. After a while, however, he begins to notice something: just as the Earth passes the red planet in orbit, it appears to ‘stop’ and loop back for a second. This is something we understand now thanks to modern science, but is enough to shake Glas’ whole faith in religion and set him on a path to heresy, starting the story anew.
Chi: Chikyuu no Undou ni Tsuite Is a Bold, Original, and Flawed Manga
As of the time of writing, Chi. -Chikyuu no Undou ni Tsuite- has only three collected volumes released, but it has already made enough of an impression to earn a whole series of accolades. Checking the series out for myself, I can see where this praise comes from: the series is bold, inventive, and original, but it does sometimes stretch author Uoto beyond the limits of his artistic abilities.
A manga about the heliocentric model may sound a little esoteric, but it does still hold relevance for us today. Do we not live in an era where faith healers still tell the vulnerable to place their hopes in God? Do we not live in an era where even the most elementary of science surrounding vaccines is being questioned due to distrust of the government?
Going back to the past and uncovering a time when science, religion, and philosophy were in conflict by reading Chi: Chikyuu no Undou ni Tsuite may provide a useful point of reflection… if approached properly.
You can read Chi: Chikyuu no Undou ni Tsuite via Big Comic Bros. The series is not currently licensed in English.