Arūpaloka, or Arūpadhātu, the heavens without form, immaterial, consisting only of mind in contemplation, being four in number, which are defined as the 四空天 Catūrūpabrahmaloka, and given as: 空無邊處 Ākāśānantyāyatana, 識無邊處 Vijñānānantyāyatana, 無所有處 Akiñcanyāyatana, 非想非非想處 Naivasaṃjñānāsaṃjñāyatana.