▻ THE QUOTATION
Let's get the quotation in front of us. Tt's from 'On the Friend', Thus Spake Zarathustra :
"One is always too many around me" - thus thinks the hermit. "Always one times one - in the long run that makes two!" ['Einer ist immer zu viel um mich' – also denkt der Einsiedler. »Immer Einmal Eins – das giebt auf die Dauer Zwei!]
I and me are always too eager in conversation : how could I stand it if there were no friend ? [Ich und Mich sind immer zu eifrig im Gespräche: wie wäre es auszuhalten, wenn es nicht einen Freund gäbe?]
For the hermit the friend is always a third : the third is the cork that prevents the conversation of the two from sinking into the depths.
Oh, there are too many depths for all hermits. That is why they long for a friend and his height. (F. Nietzsche, Thus Spake Zarathustra, tr. A. Del Caro, Cambridge : CUP, 2006, 40.)
No easy task ! How I read it is that the hermit can only self-reflect : think of a question, work out an answer, have an idea and develop or destroy it. The hermit can only conduct an internal dialogue in which s/he is both questioner and answerer, proposer and critic. 'One times one ... that makes two'. (But why only 'in the long run' - auf die Dauer?) Without the friend, as an external viewpoint or frame of reference, the internal dialogue becomes an endless self-entanglement : a self-comfort, self-torture or illusion.
As Willow Verkerk puts it : 'Nietzsche expresses the need for friends to challenge beliefs, to inspire each other into overcoming and to “a yearning for the Overhuman” (Z I: “On the Friend”)'. (Willow Verkerk, 'Nietzsche's Goal of Friendship', Journal of Nietzsche Studies, Vol. 45, No. 3 (Autumn 2014), p. 279.) How this inspiration is to come about is not clear to me.
F. Nietzsche, Thus Spake Zarathustra, tr. A. Del Caro, Cambridge : CUP, 2006.
Willow Verkerk, 'Nietzsche's Goal of Friendship', Journal of Nietzsche Studies, Vol. 45, No. 3 (Autumn 2014), pp. 279-91.
Robert C. Miner, 'Nietzsche on Friendship', Journal of Nietzsche Studies, No. 40 (AUTUMN 2010), pp. 47-69.