The metaphysical distinction between essential and contingent properties induces an epistemological distinction between two kinds of knowledge-definitional knowledge and encyclopedic knowledge. Definitional knowledge is knowledge of the essential properties of words, an encyclopedic knowledge is knowledge of contingent properties of words. On this view, the words of a language have an objective institutional status. Since words are objectively existing entities, they have essential and contingent properties. For this reason, objectivist hold that words have correct definitions-definitions that are objectively correct as a matter of institutional fact. The correspondence between words, on the one hand, and entities and categories in the world, on the other, induces a correspondence between the essential properties of words and the essential properties of those entities and categories: - Our definitional knowledge of words corresponds to the essential properties of the entities and categories that the words designate. - Our encyclopedic knowledge of words corresponds to the contingent properties of the entities and the properties that the words designate.
- Lakoff (1987), a pag.172

According to the objectivist paradigm, true knowledge of the external world can only be achieved if the system of symbols we use in thinking can accurately represent the external world. The objectivist conception of mind must therefore rule out anything that can get in the way of that: perception, which can fool us; the body, which has its frailties; society, which has its pressures and special interests; memories, which can fade; mental images, which can differ from person to person; and imagination-especially metaphor and metonymy-which cannot fit the objectively given external world.
- Lakoff (1987), a pag.183

If truth [...] is a radial concept, then so is knowledge. The best examples of knowledge are things that we know about basic-level objects, actions, and relations in the physical domain [...]. The best examples of truths are best examples of object of knowledge. We get our basic knowledge of our immediate physical environments from our basic-level interactions with environment, through perceiving, touching, and manipulating.[...] The things we feel we know best are those that can be most closely related to basic-level experience.
- Lakoff (1987), a pag.297

Knowledge, like truth, depends on understanding, most centrally on our basic-level understanding of experience. [...] What we perceive at the basic-level is taken as real and known, pending very good reasons to the contrary.
- Lakoff (1987), a pag.299