Stevens claims to reject Mackie’s aggregative move, not because it is illogical but rather because the law focuses on individual rather than aggregative responsibility.  Stevens (n 53) 131.  However, he implicitly employs it when assessing ‘substitutive’ and consequential damages for infringement of a right.  For example, if a plaintiff’s dog was killed by two stab wounds inflicted by different defendants, each of which would have been sufficient by itself to cause the death of the dog, Stevens asserts that the two defendants are each liable for ‘the value of the dog’ as ‘substitutive’ damages for their respective infringements of the plaintiff’s right to the dog, and also for any consequential damages that are a but-for result of the dog’s death, but that double recovery is not permitted since ‘he only had one right to the dog’.  Ibid 134.  Yet the but-for test can only establish each defendant’s causation of a distinct stab wound, not the death of the dog, and thus it cannot support holding either defendant liable for ‘substitutive’ damages for the full ‘value of the dog’ or for consequential damages caused by the dog’s death.  Rather, under the individually applied but-for test that Stevens claims to be applying, each defendant can only be held liable for the ‘substitutive’ value of the rights infringement that is constituted by his or her stabbing of the dog, however that might be valued, and any consequential damages (of which there likely will be none) that are a but-for result of his or her distinct rights infringement.  Moreover, although there is ‘only one right to the dog’, it is a right that each defendant has separately and distinctly infringed, and thus, under Stevens’ odd damages theory, each defendant should be fully but separately, rather than concurrently, liable for ‘substitutive’ damages for his or her distinct rights infringement, regardless of any resulting ‘double recovery’.