Since paganism is the spontaneous religion of humanity, and therefore requires no specific or divine revelation - therefore it requires no Church, no book, nor any institutions.
Paganism can be personal, individual - you can be a real pagan all by yourself.
Many people (probably) are.
And it may be better - much better - to be pagan than nothing.
There are very few pagans visible in modern societies - but who knows how many there be in the privacy of their own minds?
I have, at times, throughout my (pre-Christian) life been a real pagan in this sense - I don't suppose anybody knew about it; nor would they have been interested if I had talked of it.
By real pagan - I mean not neo-pagan: which I have also been (in a loose kind of way) at various points in my life, notably in the period from about 1998-2007.
Real pagans believe in the reality of gods, who are powerful - and must be propitiated. They believe in the reality of the soul, and that (in some way) it survives death. And they have an awe and reverence for the power and beauty of the natural world. (This list is not exhaustive.)
Neo-pagans are modern.
They have emerged since the romantic era (around the start of the 18th century) as an aesthetic movement, later a therapeutic movement - and have become visible since the early 20th century as Wicca, witches of many times, Druids, magic practices, shamanism and other 'native' spiritualities, and a general interest in and practice of past paganism.
But neo-paganism is most visible in the mass media, in the form of books, images, dramas: as a theme.
(This history has been superbly documented by the Bristol University historian Ronald Hutton - whose work I recommend highly.)
But neo-pagans have an aesthetic, an ethic, and an attitude to truth which is modern - often indeed post-modern.
The practices of neo-paganism are typically therefore aesthetic or therapeutic rather than religious.
In a nutshell - neo-paganism is about real paganism; draws from it, but does not live by it.
It is clear from observation that neo-pagans believe in the modern Western way - they believe asif - at most with suspended disbelief; and do not believe in the way everybody believed before about 1700, or the way most of the rest of the world still believes) do not believe in the reality of gods, spirits.
Neo-paganism has therefore integrated easily with modern capitalism, with political correctness, with New Age spirituality.
Indeed, neo-paganism is essentially a part of these: neither an antidote, nor oppositional to the mainstream.
Neo-paganism is an expression of nihilism - maybe emotionally pleasing, maybe able to relieve suffering - but nihilistic nonetheless.
Real paganism could - and indeed very likely will - come back again as being the spontaneous expression of human religiousness.
When it does it will be seen by its contrast with modernity, because real pagans are not PC but instead have a 'tribal' morality of courage, and a loyalty to family and chief.
They will have gods whom they fear to offend.
And pagans believe in the souls and its survival in some form after death - maybe reincarnation, sometimes a similar kind of continued life elsewhere; but often an horrible survival, or one leading inevitably to doom.
Humility and love are distinctively Christian virtues - these paganism lacks.
Existential hope is a distinctively Christian emotion - this paganism lacks.
Paganism can do great harm to the soul - especially be means of untrammelled pride seeking power.
Also, there were many noble pagans whose minds seem to adhered to Natural Law, and to have practiced love and humility, or seemed to have tenuous existential hope even despite having no reason for it.
So, from an ultimate and spiritual perspective, I am sympathetic towards real paganism.
For an atheist or agnostic to become - albeit in the privacy of their own minds - a pagan is probably progress; unless this is driven by pride and desire for power: desire to master the world and other minds.
Paganism is, for moderns, probably qualitative progress for the soul.
Paganism may keep the soul alive in a culture dedicated to its destruction.
(Of course it is not the same for a Christian. Paganism is a partial truth - crudely, Christianity minus revelation. For someone who has been or is a real Christian then to become a real pagan would be not merely be a decline but something monstrous, indeed a kind of impossibility - being in fact a turn away from good to its opposition. To abandon the higher in favour of the lower is not the same as to advance from nihilism to a partial truth. But we live in very dark times of the denial of The Good, of mainstream active opposition to The Good. Partial truth is *almost* infinitely preferable to self-reinforcing nihilism - despite its very real dangers.)