The Vedanta Sutras, commentary by Sankaracharya (SBE34), tr. by George Thibaut [1890] at sacred-texts.com
3. If it be said (that the pradhâna moves) like milk or water, (we reply that) there also (the motion is due to intelligence).
Well, the Sânkhya resumes, listen then to the following instances.--As non-sentient milk flows forth from its own nature merely for the nourishment of the young animal, and as non-sentient water, from its own nature, flows along for the benefit of mankind, so the pradhâna also, although non-intelligent, may be supposed to move from its own nature merely for the purpose of effecting the highest end of man.
This argumentation, we reply, is unsound again; for as the adherents of both doctrines admit that motion is not observed in the case of merely non-intelligent things such as chariots, &c., we infer that water and milk also move only because they are directed by intelligent powers. Scriptural passages, moreover (such as 'He who dwells in
the water and within the water, who rules the water within,' Bri. Up. III, 7, 4; and, 'By the command of that Akshara, O Gârgî, some rivers flow to the East,' &c., Bri. Up. III, 8, 9), declare that everything in this world which flows is directed by the Lord. Hence the instances of milk and water as belonging themselves to that class of cases which prove our general principle 1 cannot be used to show that the latter is too wide.--Moreover, the cow, which is an intelligent being and loves her calf, makes her milk flow by her wish to do so, and the milk is in addition drawn forth by the sucking of the calf. Nor does water move either with absolute independence--for its flow depends on the declivity of the soil and similar circumstances--or independently of an intelligent principle, for we have shown that the latter is present in all cases--If, finally, our opponent should point to Sûtra II, 1, 24 as contradicting the present Sûtra, we remark that there we have merely shown on the ground of ordinary experience that an effect may take place in itself independently of any external instrumental cause; a conclusion which does not contradict the doctrine, based on Scripture, that all effects depend on the Lord.
370:1 Viz. that whatever moves or acts does so under the influence of intelligence.--Sâdhyapakshanikshiptatvam sâdhyavati pakshe pravishtatvam eva tak ka sapakshanikshiptatvasyâpy upalakshanam, anpanyâso na vyabhikârabhûmir ity arthah. Ân. Gi.