 But this move won’t work (KKh 705–706). There are two salient ways of interpreting the definition of non-superfluity, depending on how we understand the notion of “establishing” (siddhi). According to the first, a non-superfluous condition is one which isn’t brought about independently of the effect (kāryād anyaprakāreṇa na niṣpattiḥ). But clearly a causal condition isn’t brought about by the effect; rather, it is the causal factor that contributes to the production of the effect! According to the second interpretation, a non-superfluous condition is one which isn’t cognized independently of the effect (kāryād anyaprakāreṇa na jñaptiḥ). But if this is correct, then our definition of causal relevance should predict that we always become aware of causal conditions on the basis of their effects. That’s just not true. Sometimes, we infer the existence of rain-bearing clouds on the basis of rain, but at other times, we know it simply by looking up at the sky. Setting aside these interpretations, one might claim that a condition that is non-superfluous with respect to an effect is one which isn’t brought about or known in any way other than as a causal condition relevant to that effect. But then the definition would be circular; for, now, in trying to define the notion of a causal condition, we are appealing back to that very notion.