Manusmriti - 2:87
सर्वेषां तु स नामानि कर्माणि च पृथक् पृथक् |
वेदशब्देभ्य एवादौ पृथक् संस्थाश्च निर्ममे ||
Lord Manu says, the names of things and beings and the working of their acts, as differentiated from each other, were created from the revealed word (Words in Vedas are the words of God himself).
Please check these: Excerpts from a discourse by our Sri Sri Muralidhara Swamiji