This manifestation has its own time fixed by the energy of the supreme whole, and when its time is complete, these temporary manifestations will be annihilated by the complete arrangement of the complete. There is complete facility for the small complete units, namely the living entities, to realize the complete, and all sorts of incompleteness are experienced due to incomplete knowledge of the complete. So Bhagavad-gītā contains the complete knowledge of Vedic wisdom.
All Vedic knowledge is infallible, and Hindus accept Vedic knowledge to be complete and infallible. For example, cow dung is the stool of an animal, and according to smṛti, or Vedic injunction, if one touches the stool of an animal he has to take a bath to purify himself. But in the Vedic scriptures cow dung is considered to be a purifying agent.