 Concerns about non-existent objects or non-factual states of affairs are not explicit in Parmenides’ poem, though – unsurprisingly, the goddess does not give examples of what she is proscribing. This leaves room for other construals of ‘what is not’, such as the view that it always requires completion or specification as ‘what is not F’ for some value of F, so that ‘what is not’ raises concerns about negative predication instead, especially in explanatory and cosmological contexts. But of course the precise nature of the difficulty here is not spelled out either, so speculative reconstruction is required. In any case, the goddess herself seems to use negation and the phrase ‘what is not’ quite freely, though perhaps this is just symptomatic of her liminal position at the borders of Night and Day (B1).