Will to Live and Principle of Individuation

According to Schopenhauer, the Will to Live is real, while the Individual is irreal in some respect--either a mere appearance, or an illusion, depending on the context.  That dichotomy leaves the status of his Principle of Individuation unsettled, i. e. Individuality may be irreal, but a Principle is real.  Now, one resolution of that antithesis is one that is occasionally implicit in some of his passages, and is sometimes made explicit by Nietzsche--the need for illusions.  Regardless, Schopenhauer does not seem to consider that a Species propagates itself by reproducing itself.  In other words, the Will to Live and the Principle of Individuation are one and the same for a Species.  So, a generally unrecognized innovation of Schopenhauer's system is that it grounds the Principle of Individuation, a difficult problem in a system the basis of which is a self-sufficient entity, e. g. Leibniz', which does not explain why there is something other than his deity, rather than nothing else.