When Krsna left for his transcendental abode all religious principles and knowledge also went with Him. And that was the situation. (Sanskrit) And therefore in this age of Kali, all vision was lost! This means all understanding of the truth, of what is the goal of life: or how to conduct oneself in life was lost.
But it will again re-emerge by the sound from the Srimad Bhagavatam.
(Kadamba Kanana Swami , Radhadesh 04/2010)