Halakhah for Sanhedrin 134:16

And it is possible that a hint will come up in our hands from the roots of the forbidden mixtures of seeds and animals and shatnez (the mixture of linen and wool). And we will write at length about them in their places, with God's help. And that which they, may their memory be blessed, said (Sanhedrin 67b, Chullin 7b), “Why is its name called kishufim (magic)? Because it contradicts the retinue (makhishin pamaliah) on high and on low,” is meaning to say that their power temporarily overrides the power of those forces appointed over them. And see the precision of their words, may their memory blessed, as they said, “the retinue on high,” and they did not say, “the decree of High – since God, blessed be He, decreed it and wanted from the beginning of creation that this action would come out from the two of them when they are mixed. And there is an open rebuke from it towards those appointed over them [about their lack of absolute power]. Rather, they said that the power of the retinue on high is [that which is] contradicted regardless. And one, whose intellect is close to the light of the face of the King and the power of his merit overrides the power of those appointed, will not fear from this phenomenon, as we found that the sage said to the witch in the Gemara (Shabbat 81, Sanhedrin 67b).