Language, language development, language acquisition ....

And biology and economics are on the same level (2) and also not on the same level (II and III):

Physics: 1a and Ib.
Chemistry: 1b and IIa.
Biology: 2a and IIb.
Economics: 2b and IIIa.
Semiotics: 3a and IIIb.
Linguistics: 3b and IVa.
Philosophy: 4a and IVb.
Mathematics: 4b and Ia.

  1. Anorganic.
  2. Organic.
  3. Mental.
  4. Spriritual.
    I) Order (means mainly ordinary mode of being).
    II) Matter (means mainly material mode of being).
    III) Function (means mainly functional mode of being).
    IV) Consciousness (means mainly conscious or phenomenal mode of being).