Every part is also a whole. The cell is a whole entity made from smaller wholes (atoms) and comprising larger wholes (organs). The same goes for the atom, our society, the planet and our Milky Way galaxy. At each level, we see wholes that are also communities of parts. These whole/part structure-relationships were termed ‘holons’ by Arthur Koestler.
…particles, atoms, molecules, cells, tissues, organs, organ systems, organism, society, ecosystem, planet, solar system, galaxy, local group, supercluster, observable universe, cosmos…
If we proceed even beyond elementary particles to ‘smaller’ scales, an unexpected finding is revealed. Elementary particles are not made from smaller things - they are aspects of vast fields extending throughout space, like wrinkles in a vast bedsheet.
These facts challenge our concept of a discrete ‘thing’, since every ‘thing’ is a holon in a hierarchy of holons. The line delineating my finger disappears into the boundaries of cells, which in turn disappears into the boundaries of electron fields. No boundary is fixed and final.