Parallel to the theories of Bergson, embraced by Metzinger, Gleizes and other members of the Section d'Or, Maeterlinck’s ideas became of interest. Bolstered by mathematics, Reimannian geometry, and new discoveries in science that revealed existence of unseen realms (such as X-rays), and attracted to the concept of extra dimension (in addition the three spatial dimensions), Metzinger likely responded positively to Maeterlinck’s popular play L’Oiseau bleu (written in 1908), finding in it, perhaps, the analogy to the Cubist quest for higher realities.
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