«Gender can be grasped only by means of morphology; its existence depends in turn on the size and shape of the dual world it structures. A snail, after adding a number of widening rings to the delicate structure of its shell, suddenly brings its accustomed building activities to a stop. A single additional ring would increase the size of the shell sixteen times. Instead of contributing to the welfare of the snail, it would burden the creature with such an excess of weight that any increase in its productivity would henceforth be literally outweighed by the task of coping with the difficulties created by enlarging the shell beyond the limits set by its purpose. At that point, the problems of overgrowth begin to multiply geometrically, while the snail’s biological capacity can at best be extended arithmetically. So gender sets limits to the social structure it forms, a structure expressed in every aspect of life-style, but first of all in kinship.»
– Ivan Illich, “Le Genre vernaculaire” , in Oevres complètes, vol. 2, Paris: Fayard 2005, p.192 [Translated by Ronnie Richards].