pathwaydependent

Pathway-dependent refers to properties or outcomes of a system that depend on the sequence of steps or pathways taken, rather than solely on the initial state or the final target. The term emphasizes historical contingency, meaning that the same starting conditions can lead to different results if the processing route differs. Pathway dependence is related to, but distinct from, general path dependence, which describes a broader tendency for systems to follow a particular trajectory due to cumulative effects.

In biology and chemistry, pathway-dependent behavior describes how intermediate states, regulatory events, and stepwise branching determine which routes are utilized. This can affect metabolic flux, signaling outcomes, and the ultimate products produced. For example, sequential activation of signaling pathways or irreversible steps can create a memory of prior cues that biases subsequent responses.

In the social sciences and economics, pathway dependence explains how early choices, standards, institutions, or technologies constrain later options, sometimes producing lock-in or persistent effects even when better alternatives exist. Historical accidents or path-by-path comparisons can yield divergent trajectories from similar starting conditions.

Limitations: not all processes are pathway-dependent; many systems are dominated by current conditions and stochastic variation. As a framing, pathway dependence highlights the role of sequence and history in outcomes.

See also: path dependence, hysteresis, historical contingency.