In tort law, a plaintiff must establish not only that the defendant's conduct was a cause-in-fact of an injury but also that it was the 'proximate cause.' Cause-in-fact asks whether the harm would have occurred 'but for' the defendant's act. Proximate cause, by contrast, is a policy-driven limitation: even where an act sets a chain of events in motion, liability extends only to harms that were a reasonably foreseeable consequence of the conduct. When the connection between the act and the ultimate injury is so attenuated, or the intervening events so freakish, that no reasonable person would have anticipated them, courts hold that proximate cause is lacking and the defendant escapes liability. The doctrine thus prevents a negligent actor from being held responsible for every remote and bizarre outcome that can be traced, however indirectly, to the original act.