Vedanta
Upanishads: The only cause of suffering is the first one mentioned above, that is, not knowing the true nature of reality.
Buddhism: Buddhism is centered on the alleviation of human suffering. The causes of suffering, and the way out of suffering.
Buddhism/Vedanta:
Look back at your footsteps, and see yourself.
Every state of consciousness projects its own reality. And there are various states.
Consciousness (Projection of Reality)
1 Deep sleep (limited; can respond to the cry of fire, a mother can respond to the cry of her baby, etc.; spirit is in surveillance).
2 Dreams (more repertoire of experience, of karmic software; while dreaming all real, be it joy, pain, fear, etc; when we wake up we realize it was not real (note-1: insight of the dream occurs after the dream, not during the dream; note-2: after dream, we wake up to another dream, the waking state of consciousness)
3 Waking state of consciousness (In it, perception is equally transitory, ephemeral, etc. Feeling can be similar as in a dream, that is, joy, pain, fear, etc;)
4, 5, 6: I have not yet grasped these additional three states, and hence been unable to summarizie them. (Ajay)
Source: Discussion between Robert Thurman (Writer; Buddhist Scholar; Professor, Columbia University) and Prem Chopra (Writer; Hindu Scholar; Doctor)