The definition of life contains both biological systems and their environment: therefore every living system follows life processes and exhibits systemic attributes. The synthetic exposition of the main modern scientific paradigms (from hierarchic structure to non-equilibrium thermodynamics) demonstrates the central significance of history to better understand living systems. All these premises allow to understand the present scientific situation in vegetation science, in which serious limitations of the phytosociological approach appear, especially in landscape investigation. The theoretical revision of life organisation characters and basic transformation processes of ecological systems lead to consider more advanced transformation and metastability processes even in vegetation: from community dynamics to biological territorial capacity of vegetated units. This more theoretical and critical section is followed by rather innovative statements, proposing new criteria to overcome deterministic interpretation (e.g. potential vegetation) in the study of vegetation and landscape. In conclusion, the first statements by Braun-Blanquet (1928) maintain their significance as basic concepts in describing vegetation, but are in need to be integrated in the general scientific theory.