It occurs to me that “I love you” demonstrates Wittgenstein’s theory about language gaining its meaning through use.
To begin with, I suspect that on a micro-level, just saying “I” is more of a complex matter than is often recognized. I think that when a person says “I,” they are (albeit near-instantaneously, and only semi-consciously) looking back on a whole collection of thoughts thought, feelings felt, perceptions registered, and actions taken, and deciding to consider them all as centered on a self, an “I,” that is the speaker’s own. Then too, saying “you” as if the speaker knows what it means makes a whole bunch of assumptions. As anyone who has had a first crush knows, we often don’t perceive people as who they really turn out to be. And the verb “love”? Of course we could spend all day defining that.
But what old Ludwig would have us notice most, I think, is how the whole sentence, “I love you,” gets used, in American English at least (for it varies in different language communities). Of course it can express affection of various kinds, to a romantic partner, a friend, or a child. It can also mean “I completely agree with your unexpected remark,” when said to a coworker or acquaintance; convey reassurance as the signoff to a phone call; or in negative relationship interactions, carry with it the unspoken, but clearly understood coda, “and therefore you must do what I want” or “therefore you must excuse my misdeeds.”
Thinking about this all last night reminded me of an Annie Lennox song, introduced to me long ago by a man with whom, for a few years, I exchanged those words, in many of their uses. I only noticed after it began to play that the second line of its chorus speaks of the disappearance of language itself; maybe it means to say that “I love you” is indeed exemplary of what language does. It creates speakers and addressees, and connects them, for good and ill, around matters of the heart.