Humans live on the Blue Planet: seventy per cent of ‘Earth’ is covered by oceans. We increasingly hear these descriptions: that oceans are the largest habitat, that eighty per cent of all species live there, that they determine weather and climate. All of which, and much more, is true. But the meaning of this still fails to find purchase with most people. The edited volume Tidalectics – subtitled ‘Imagining an oceanic worldview through art and science’, and compiling a pelagic compendium to unsettle and then reconfigure assumed certainties – engages with this challenge.