causation

1. the act of causing something or creating a result or effect. In torts, in particular, parties must prove that a defendant’s wrongful conduct actually caused some damage or injury.

Usages

But for causation:  In tort law, the most common example is “but-for” causation. That is, the injury would not have occurred but for the defendant’s acts or omissions.

Example: Jack would not have hurt herself but for Jill spilling the pale of water.

substantial factor: Sometimes, multiple causes for an injury are intermingled and utterly indistinguishable. If the start of two loud motorcycles cause a horse to rear and throw its rider, then each motorcyclist was a substantial factor in causing the harm. If a person is exposed to two or more asbestos, tobacco, or other harmful substances, the separate product makers may be substantial causes for the aggregate injuries over time.