According to Osho, habit is nurture—copied from society, programmable and droppable; it only masquerades as ‘second nature.’ Instinct is inborn, the lowest layer of your nature, shared with animals. Human nature is a spectrum from instinct to intellect to intuition (heart) and finally turiya, the nameless fourth—your unchangeable essence where the individual meets the universal; meditation opens the higher layers.
Habits are learned and can be changed, instincts are the built‑in animal part, and human nature is the whole ladder from those drives up to loving wisdom and a silent oneness inside.