Śrīpāda Rāmānujācārya gives the example that when a green bird enters a green tree it does not become one with the tree: it retains its identity as a bird, although it appears to merge in the greenness of the tree. To give another example, an animal that enters a forest keeps its individuality, although apparently the beast merges in the forest. Similarly, in material existence, both the material energy and the living entities of the marginal potency maintain their individuality. Thus although the energies of the Supreme Personality of Godhead interact within the cosmic manifestation, each keeps its separate individual existence. Merging in the material or spiritual energies, therefore, does not involve loss of individuality. According to Śrī Rāmānujapāda’s theory of Viśiṣṭādvaita, although all the energies of the Lord are one, each keeps its individuality (vaiśiṣṭya).
Ref >> Srila Prabhupada Vani.