Cum maxime unusquisque homo suum utile quaerit, tum maxime homines sunt sibi invicem utiles. Note su Ethica IV, prop. 35 e corollari

The paper concerns the crucial categories of the fourth part of Spinoza's Ethica. In the opinion of the author, Spinoza's definition of "utility" and, more widely, his views on practical reason are quite original and based on the ontological notion of "convenance" (convenientia) which is not easy to reduce to the classical ends/means view of utility. In the opinion of the author, Spinoza is trying to ground a crucial point of Ethics, part IV: only a person which is useful to herself can be really useful even for me.