From Late Thoughts, a chapter towards the end of Jung's classic memoir Memories, Dreams, Reflections.
I falter before the task of finding the language that might adequately express the incalculable paradoxes of love. Eros is a kosmogonos, a creator and father-mother of all higher paradoxes of all higher consciousness. I sometimes feel that Paul's words -- "Though I speak with the tongues of men and angels, and have not love" -- might well be the first condition of all cognition and the quintessence of divinity itself. Whatever the learned interpretation may be of the sentence "God is love," the words affirm the complexio oppositorum of the Godhead.
In my medical experience as well as in my own life I have again and again been faced with the mystery of love, and have never been able to explain what it is. Like Job, I have had to "lay my hand on my mouth. I have spoken once, and I will not answer."
You have to like the genuine humility, the not knowing, though I do wonder how in that state he couild help his love-stricken patients find their way through the mystery and the bewilderment of love.
[image from the irreplaceable David Levine of the 1965 NYRB: available here]
Reminds me of an apparently very famous quote from the 20th century philosopher Wittgenstein, of the same era and similar background, who described his first great book about knowing and the metaphysical by saying in conversation, as described in a recent NYTimes review:
What can be said at all can be said clearly, and what we cannot talk about, we must pass over in silence.
"Thus the philosopher Ludwig Wittgenstein summarized his first, notoriously difficult book,’Tractatus Logico-Philosophicus.” Wittgenstein’s declaration is usually taken to mean that talk about anything metaphysical — God or gods, supernatural phenomena, mystical experience — collapses into nonsense under scrutiny."
For Jung, it's easier to talk about God and the unconscious than love and sex. For Wittgenstein, it's easier to talk about talking about God than either God or the unconscious or love and sex.
Jung has no difficulty admitting he cannot talk about love -- for reasons professional and personal. Is this admirable, or a bit of an evasion I wonder?