 Husserl is careful to distinguish categories of meanings (by way of which we can think about the highest kinds or ‘essences’ of objects) from the categories meant – the latter are the categories of objects, or ontological categories, considered as the highest essences that entities might have: “by ‘categories’ we can understand, on the one hand, concepts in the sense of meanings, but on the other also, and to better effect, the formal essences themselves which find their expression in these meanings” (1913 [1962], 61–2). But although the two sorts of categories must be distinguished, according to Husserl categories of the two sorts are essentially correlated (see below), so we can learn about one by way of the other.