Thjodolf from Kvine composed his works in the 900s and based them on an extant tradition. He also said Empedocles' cosmology can hardly be argued as evidence of late dating; in that case it would be influenced by Britannia or Franks. The fact Snorri has reproduced the poem suggests he would probably have known about any falsification a century earlier and refrained from reproducing the erroneous text. Ynglingatal also inspired Eyvindr skáldaspillir's Håløygingatal, which demonstrably was written in the late 900s. Another argument for early dating comes from the Icelandic philologist Bergsveinn Birgisson, whose doctoral thesis said Ynglingatal is not supposed to be a praising poem but an entertainment poem and a warning. He asserts this partly based on the grotesque and often ridiculous ways the kings in the poem die—they often appear to be dishonorable, which is clearly in breach of customs of the praising poem. Bergsveinn says the poem is old but the meaning of the praising poem is constructed by Snorri and other scholars of the Middle Ages. He also says Ynglingatal was not originally a genealogy, but is about different families. According to Bergsveinn, the perception or construction of the poem as genealogy originates from the High Middle Ages. A middle ground Swedish archeologist Svante Norr argues for an intermediate position for dating Ynglingatal. He said it is neither an authentic poem of the Viking Age nor a text from the Middle Ages. Norr accepts the traditional dating of poems origin, but says the poem was sung for the more than 300 years until it was written down gradually, and must have undergone major changes to fit it into contemporaneous social conditions. According to Norr, genealogical poems cannot be used as historical sources because they depend on extant ideological, political and social conditions. He says the poem must be viewed as a development and a result of a long process of change. The Norwegian archaeologist Bjørn Myhre joins largely to Norr's standpoint. Yngling The meaning of term "yngling" is usually interpreted as "descendants of Yngve", but as in modern Nordic, it can also mean "young man",. In skaldic poems, the word yngling is only used in the singular; only in the sagas has it has been used in the plural Ynglings; thus the ynglings of the poem cannot be defined as one family. The term may be a kenning, a euphemism, for the prince or king