Cohle says: "Time is a flat circle". This is Friedrich Nietzsche's doctrine of eternal recurrence, as depicted in The Gay Science and Thus Spoke Zarathustra. Cohle expresses this idea in a pessimistic mood and it is meant to magnify the absurdity of life by declaring its endless repetitionEhh. A flat circle is called a disc. Why not say "time is a disc" and save yourself a lot of bother. You'd surely realise what you're saying doesn't make any sense. Unless you're talking about clockfaces - or possibly the disc in an old style parking meter. Is that where you heard it? At a watch and clock shop?