yas tu yasyādir antaś ca
sa vai madhyaṁ ca tasya san
vikāro vyavahārārtho
yathā taijasa-pārthivāḥ
yaḥ - which (cause); tu - and; yasya - of which (product); ādiḥ - the beginning; antaḥ - the end; ca - and; saḥ - that; vai - indeed; madhyam - the middle; ca - and; tasya - of that product; san - being (real); vikāraḥ - the transformation; vyavahāra-arthaḥ - for ordinary purposes; yathā - as; taijasa - things produced from gold (which is itself derived from fire); pārthivaḥ - and things produced from earth.
The Lord here explains that the original cause is certainly present in its effect, citing the example of gold and clay functioning as the causal ingredients of many different products in which gold and clay continue to be present. For our convenience, we assign different names to temporary products, although their essential nature continues to be that of the ingredient, and not of the temporary product.