Este esfuerzo por conseguir que cada cual apruebe aquello que uno ama u odia es, en realidad, ambición; y así vemos que cada cual apetece, por natura… - Benedictus de Spinoza

...Kant is Spinoza's only adversary in the realm of occidental culture. Constantin Bruner has aptly stated that everyone must be either a Spinozist or a Kantian. The modern intellectual world, however, is overwhelmingly Spinozistic. Kant created only a school of thought, but Spinoza gave birth to a new culture and religion. Kant was long forgotten in his own fatherland until he was revived by Hermann Cohen. Spinoza has always lived in the centers of modern culture. Although at first he was maligned, calumniated, and even damned, he came to be later blessed and admired. He was always a subject of discussion in religious, philosophical, and scientific circles, because he dangled before man's eye the picture of a world without contradictions or abuses. Kant has accomplished only a special task. He examined and described the mechanism of the human mind rather than the mechanism of the world. He can be compared to Aristotle, as Spinoza can be likened to Plato. Kant is the very embodiment of idealism, while Spinoza is the representative of extreme naturalism.

...Now Spinoza, my master and model in respect to the first point [the natural basis of morality], does not satisfy me on the second [the humane possibilities, the "types of excellence towards which life may be directed"]; and I will take this opportunity, since I may not have any other, of clearing my conscience of ambiguity in that respect. The complete moralist must not only be sound in physics, but must be inwardly inspired by a normal human soul and an adequate human tradition; he must be a complete humanist in a complete naturalist. Spinoza was not only a complete naturalist but, by a rare combination, also a spiritual man, seeing and accepting the place of the human heart in the universe; accepting it not grudgingly or viciously or frivolously, as your worldling does, but humbly and joyously: humbly in that he asked to be nothing more than he was, and joyously because what he was allowed him, in spirit, to salute and to worship every form of the good. Nevertheless, Spinoza was not a complete humanist. He had no idea of human greatness and no sympathy with human sorrow. His notion of the soul was too plebeian and too quietistic. He was a Jew not of Exodus or Kings but of Amsterdam. He was too Dutch, too much the merchant and artisan, with nothing of the soldier, the poet, the prince, or the lover. [...] He was virtuous but not normal. [...] He was a genius; but as a guide in the spiritual life, he was narrow and inadequate.

Surely, Spinoza's parallelism of attributes expressing differently but equivalently one and the same substance was a feat of genius and far superior to all other treatments of the problem at the time. Without interposing a synchronizing deity, as did others, it overcame Descartes' dualistic rift by a monistic reduction, yet retained the full severity of the disjunctions which that dualism had been designed to ensure.