Posadism is a Trotskyist movement that emerged in the mid-1950s to early 1960s, splitting from the International Secretariat of the Fourth International due to disagreement over many unpopular and fringe issues, notably enthusiasm for nuclear war as an accelerationist revolutionary method.
Following the formation of the Fourth International Posadist in 1962, the ideology continued to incorporate their membership's New Age, ufologist, and other unorthodox beliefs into a framework of Marxist determinism. Many overlap with transhumanist and cosmist interests, including space exploration and habitation, interspecies communication, cloning, and radical life extension.
In recent years, Posadism has enjoyed a renewed popularity in online political discussions, largely as an ironic, satirical, or strawman position. Modern reinterpretations such as Anarcho-Posadism arrive at similar conclusions while utilizing different interpretive frameworks. These also borrow from (and to an extent overlap with) newer political movements, such as libertarian and anarchist transhumanism, right-accelerationism, and primitivism, occasionally synthesizing positions that would otherwise be seen as mutually exclusive.