Horizonnen

Horizonnen is a term used in speculative thought and interdisciplinary discourse to denote a set of boundary concepts that delimit what can be observed, known, or achieved within a system. The word is a neologism inspired by the horizon, adapted to function as a plural noun that signals multiple limits rather than a single edge.

In practice, horizontonnen are commonly divided into two categories: spatial horizontonnen, which describe physical or geographic limits of a space or environment, and epistemic horizontonnen, which describe the boundaries of knowledge, data, or understanding. The concept is used in science fiction, urban planning, and policy analysis to frame long-term thinking and risk assessment. It helps writers and planners articulate what lies beyond current perception and what would be required to reach it.

Critics argue that horizontonnen can blur distinct kinds of limits, from material constraints to cognitive biases, if treated as a single framework. Proponents maintain that the term provides a useful heuristic for organizing discussions about futures, technologies, and climate resilience. The idea has influenced worldbuilding, scenario planning, and academic debates about the scope of human capability.

See also: horizon, horizon line, long-term horizon, epistemic boundary.