Instinct is found in humans, animals and birds. In birds, the ego does not interfere with the free divine flow and divine play. Hence the work done by them through their instincts is more perfect than that done by human beings. Have you not noticed the excellent work done by birds in their building of wonderful nests?
When we are a child, the Ego is not very potent. It is like a shadow in a glass. So only we love the innocence of the children, and always want to live like them. The moment this little ‘I’ becomes stronger in us in adolescence, it entangle us in the achievement of various worldly desires (power, name, fame), side by side, various sorts of fears, various sorts of desires, a host of delusions take firm hold of us. The world appears to you more real, too.
Mind exactly identifies itself with the human and feels itself to be ‘I’ and hence thinks, I am in bondage. The egoistic mind is the root of bondage. The non-egoistic mind is the root of Moksha / Nirvana / Self Realization.