Full Idea
I once began reading a philosophical article on love. The following statement soon came up: 'Bob loves Kate if and only if...' At that point I stopped reading. Such a formalized approach was unsuitable, because the actual phenomenon would be lost.
Gist of Idea
You can't understand love in terms of 'if and only if...'
Source
Lars Svendsen (A Philosophy of Boredom [2005], Pref)
Book Reference
Svendsen,Lars: 'A Philosophy of Boredom' [Reaktion Books 2005], p.8
A Reaction
It is hard to disagree! However, if your best friend comes to you and says, 'I can't decide whether I am really in love with Kate; what do you think?', how are you going to respond. You offer 'if and only if..', but in a warm and sympathetic way!