In the end it is the contract that makes the difference between the insider and the outsider of an organisation

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Somehow the difference between the insider and the outsider of an organisation is the contract. The formal agreement to contribute to the organisation and to gain some benefits out of it.

Maybe it is as simple as that.

Whether it is your membership or your employment contract, there is a formal element to being part of an organisation.

And that formality is part of what defines the border, in a rather fundamental way.