LotR -- Book 1 - Chapter 02 - The Shadow of the Past

[The Saucepan Man]

If it could then we have a universe where evil is a power in its own right, potentially strong enough to defeat good in a straight battle (=Manichaeanism). If evil can only defeat us because of our 'fallen' nature, then its our fallen nature itself which brings about our defeat (=Boethianism).

But, if Man is “fallen”, doesn’t this in itself imply the existence of evil as a separate power in its own right, since the “fall” of Man could only have been brought about by the intervention of evil (as an element of the external conflict between good and evil)? If so, then it seems to me that there is in practice little distinction between these two propositions. Either way, the inevitability of Man’s ultimate submission to the Ring (as explained by Gandalf in the passage quoted above) is brought about by the interference of an external evil power.