In the seventeenth century when Rene Descartes divided everything in the universe into two realms as "Res Extensa" (matter) and "Res Cogitans" (mind), gathering knowledge within the realm of Res Extensa was called Science and the phenomenon of reincarnation got pushed into the other realm Res Cogitans which was condemned to be not respectable and not up to the dignity of Scientists to probe into. Science was considered the respectable realm to study.