Almost everybody who believes-in the evolution of human consciousness, also believes-in reincarnation - but not me.
While I think it probable that reincarnation was usual before the advent of Jesus Christ; I don't believe that reincarnation has been normal since then, at least among Christians - and has indeed been very exceptional (or absent). This for the simple reason that Jesus came to bring resurrected and eternal life in Heaven to his followers, and my assumption is that resurrection happens soon after biological death - which combination (as I understand it) rules-out reincarnation. (although perhaps not something like projected avatars...).
However I also believe that through history (and pre-history) the consciousness of men has developed according to a divine plan or destiny (consciousness has 'evolved' in an old sense of the word). In other words, Men at different points in history have thought and experienced differently - and this is evolutionary-development of mind is (of course) reflected in language (as documented by the work of Owen Barfield), religion, society, science, art and everything else.
But the key point is that socio-cultural change is driven by the inner change in human consciouness - and that inner change has inner causes - and not (or not primarily) the other way around (as most people suppose).
However, if for the past c. 2000 years at least, human souls have one mortal life, and if therefore we can experience only one mode of consciousness and one era of evolutionary history - then what is the value of an evolution in consciousness? Why have consciousness changing through human generations - if, for each individual person - consciousness is Not changing?
My answer is that each of us is unique, therefore each of us needs different experiences in our (one) mortal life; and the evolution of consciousness is a way that God uses to give individual human spirits the many types of experience that each needs.
Other ways of providing different experiences come from different families, different social circumstances, nations, levels and types of civilisation etc. But one of the important ways in which mortal life is tailored to the needs of individual incarnating spirits is through the phases and stages of the development of consciousness.
So that the simple hunter gatherer societies had (in important respects) a very young-child-like consciousness even among adults. Medieval Europe was essentially rooted in the developmental stage of an older child (with its fixed symbolism, hierarchies and rituals). Modern society is essentially the adolescent stage.
And there has never yet been (except among individuals and small temporary groups, perhaps) any time and place where the adult form of consciousness has prevailed - although that is the task of our stage of evolution: i.e. to become properly adult in our consciousness.
Our task (here and now, in The West) is to grow-up spiritually; to attain (and this must be an active and conscious choice, which is a reason why it has not yet happened) what Owen Barfield called Final Participation.
