Here Strabo launched another quibble. Hipparchus, relying on Pytheas, according to Strabo, placed this area south of Britain, but he, Strabo, calculated that it was north of Ireland (Ierne/Ἰέρνη). Pytheas, however, rightly knew what is now Scotland as part of Britain, land of the Picts, even though north of Ireland/Ierne. North of southern Scotland the longest day is 19 hours. Strabo, based on theory alone, states that Ierne is so cold that any lands north of it must be uninhabited. In the hindsight given to moderns Pytheas, in relying on observation in the field, appears more scientific than Strabo, who discounted the findings of others merely because of their strangeness to him. The ultimate cause of his skepticism is simply that he did not believe Scandinavia could exist. This disbelief may also be the cause of alteration of Pytheas' data.