His alternative system spread through most of Europe during the 13th century .
Alpetragius also declared the Ptolemaic system as an imaginary model that was successful at predicting planetary positions but not real or physical .
Alpetragius ' alternative system spread through most of Europe during the 13th century .
Alpetragius also declared the Ptolemaic system as an imaginary model that was successful at predicting planetary positions but not real or physical .