 While Kant saw these organising categories as fixed and universal, Berlin believed that they are, to different degrees, varying, transient or malleable. ‘All our categories are, in theory, subject to change’ (2002b, 144, note 1). No categories are wholly prior to, or independent of, experience, even though in practice some of them are pragmatically fixed, whether by the world or by our minds or both. Rather, the ideas in terms of which we make sense of the world are closely tied up with our experiences: they shape those experiences, and are shaped by them, and as experience varies from one time and place to another, so do basic  concepts.[2]  Recognition of the basic concepts and categories of human experience differs both from the acquisition of empirical information and from deductive reasoning, for the categories are logically prior to, presupposed by, both.