unforeseeability

Unforeseeability is the quality or condition of being not able to be foreseen or predicted. It refers to events or consequences that could not reasonably be anticipated given the information and standards available at the time. In everyday usage, unforeseeability is used to describe unexpected outcomes or uncertainties in planning, risk assessment, and decision making.

In law, foreseeability is a standard that governs liability and damages. In many jurisdictions, a defendant is only liable for harms that were reasonably foreseeable as a probable result of their conduct. This "foreseeability test" is central to establishing negligence and proximate cause. For example, in tort law, damages are typically limited to those that a reasonable person would anticipate. In contract and commercial law, the principle limits recoverable damages to those that were reasonably foreseeable by the parties at the time of contract, as illustrated by the Hadley v Baxendale rule on consequent damages.

In risk management and policy, unforeseeability highlights limits of prediction and the challenge of planning for rare or unprecedented events. Scholars distinguish between predictable risks, low-probability events, and radical uncertainty, emphasizing the use of scenario planning and robust design to mitigate unforeseeable outcomes. In philosophy, unforeseen events raise questions about the ability to know future states, the reliability of predictions, and the nature of epistemic limits.

Examples of unforeseeable events include natural disasters of unusual scale, sudden market shocks, or novel technologies that create unforeseen side effects. Although no event can be guaranteed as impossible to foresee, the term denotes that, under reasonable standards, it was not anticipated.