This is an effort to think through the ‘computational ocean’. Computer science scholars Denning and Tedre argue computational thinking is not a recent development but, rather, emerged from thousands of years of expertise, critical analysis, and interpretation. Its current professionalised state, however, appears fixed on attempting to understand the world through speed of calculation and elimination of human error. Computational thinking manifests widely in Earth Systems governance via complex algorithms, non-linear logics, and increasingly automated systems of knowledge production. This is especially so for Ocean governance, whose own foundational characteristics - impossibly vast scale, unruly ecologies, and planetary dynamics - seem to call for an extra-human capacity in data collection and explication. A computational ocean is a problem though because its governance has, is, and always will be non-rational, largely as a result of its dependence on technologies. Modelling relies on prediction, which overwhelmingly consists of ‘unknown unknowns’ in oceanspace and such gaps lead to contingent understanding at best. This could (potentially) result in positive forms of relational governance, but instead has mainstreamed risk responses to ongoing unpredictability. Panic, anxiety and erratic behaviour thus come to dominate the apparatus of the ocean. This is frightening and requires further theorisation. As Stanisław Lem wrote in Solaris (1961), “We have no need of other worlds. We need mirrors. We don't know what to do with other worlds. A single world, our own, suffices us; but we can't accept it for what it is.”