Did Jung believe the “collective unconscious” was an actual, independent thing? Chickens & eggs: did he feel the collective unconscious exists as an exterior entity which we tap into and thus influences our perception, or did he feel it was created in individual minds as a product of similar thought processes to common experiences in a manner akin to parallel evolution?
And a bonus question: what are the key differences between the collective unconscious, and spiritus mundi?
The latter - he believed it was inherited, a set of instinctual archetypes arising from the experiences of primitive man - not a “live stream”, as the kids would say.
Which “spiritus mundi” ? Yeats in The Second Coming used it in a sense larger than Jung’s CO, more like the first meaning of CO you asked about. But it also gets used a bit more like zeitgeist sometimes.