 This contextualist approach to assigning 1-intensions is incompatible with the Core Thesis (Chalmers 2004, 167­–176). Consider sentences like ‘Language exists’ or ‘A sentient being exists’: the meaning of these sentences seems to guarantee that they will be true in every possible context in which they are used. So on the contextualist approach, these sentences should be assigned necessary 1-intensions, mapping every possible context of use to the truth-value True. But contrary to the Core Thesis, these sentences are not apriori truths knowable independently of any empirical evidence. There’s no contradiction in the very idea of a world without language or thought and we can easily imagine what such a world would be like; it’s just that our everyday experience allows us to immediately rule out the possibility that our actual environment is like that. The problem is that contextualist 1-intensions are undefined for worlds without thought or language, even though they are both apriori coherent and metaphysically possible. So a necessary contextual 1-intension does not track apriority or metaphysical necessity. Contextualist 1-intensions, therefore, cannot satisfy the rationalist’s Core  Thesis.[17]