In the first paragraph of this article about friendship, I encountered the following sentence:
Already the characteristically modern relationship, it [friendship] has in recent decades become the universal one: the form of connection in terms of which all others are understood, against which they are all measured, into which they have all dissolved.
I am struggling to understand what this sentence is trying to convey, especially the bolded part. My guess is that it means
(1) Any other people are considered friend if and only if I understand them.
(2) I always evaluate other people using friendship as the only measure. That is, I always divide all other people into two groups: friends and non-friends, and there exists no third catagory.
(3) Once someone becomes my friend, he/she is integrated(dissolve) into a large homogeneous group, namely friends, and is not treated as a separate person any more.
I am particularly not sure about the second and the third points, while not 100% sure about the first point as well. If anyone understand this sentence I will be grateful for any help.