Here’s Dermot Moran’s explanation of our shared interrelation. He even pulls from Scheler,
Other phenomenologists also emphasize human collectivity even in isolation. Max Scheler writes, in his classic Formalism in Ethics (1916/1973), that even Robinson Crusoe was never completely alone; he brought with him into solitude all the language, ideas, skills, clothing, of his seventeenth-century world. Scheler writes:
An imaginary Robinson Crusoe еndowed with cognitive-theoretica1 faculties would also со-ехрeriеnсе his being а member of а social unit in his experiencing the lack of fulfillment of acts of act-types constituting а person iп general. (Scheler 1973, 521)
In the Nature of Sympathy (1923/1954), Scheler clarifies further:
Robinson Crusoe would never think: ‘There is no community and I belong to none : I am alone in the world’. He would not only possess the notion and idea of community, but would also think: ‘I know that there is a community, and that I belong to one (or several such); but I am unacquainted with the individuals comprising them, and with the empirical groups of such individuals which constitute the community as it actually exists.’ (Scheler, 1954, 234)
Humans are intrinsically social even if there are no ‘others’ in my immediate community. Indeed, solitude can only ever be an artificial state. One needs extraordinary discipline – to maintain silence, to lose physical contact with other human beings. Indeed, unless it is explicitly chosen as a methodological way to gain access to oneself, solitary confinement is a punishment – a torture for human beings. Part of the key to coping with living in solitude is structured routine and tremendous mental discipline.