The Doctrine of a single substance, which is the cause of itself, i.e God and nature at the same time belongs to __ Select one answer: Spinoza Feuerbach Leibniz Descartes

The correct answer is Spinoza.<br /><br />The Doctrine of a single substance, which is the cause of itself, i.e., God and nature at the same time, belongs to Spinoza. This concept is central to Spinoza's philosophy, where he posits that there is only one substance, which he calls "God or Nature," and that everything else is a mode or attribute of this single substance.