Science of Self-Realization

Meaning of Science of Realization

Hare Krishna!

I am aware about the realization part but What does the "Science " part mean in the term Science of Realization


Question about how to understand past lifes.

Does it say anything in the vedas about how we can detect past lifes? One thing is mind and memory but do the vedas say anything about some sort of light that is realizing the external reality of a child into what happend to it in the past? There is a quote about that everything will be shown in the light by christ, why not our past as well?