When we asked how Spock and Kirk regard one another, what in fact their relationship consists of in texture, Gene Roddenberry said:
’…I definitely designed it as a love relationship. And I hope that for men…who have been afraid of such relationships…that they [Spock and Kirk] would encourage them to be able to feel love and affection, true affection…love, friendship and deep respect. That was the relationship I tried to draw. I think I also tried to draw a feeling of belief that very few of us are complete unto ourselves. It’s quite a lovely thing…where two halves make a whole.’
— Star Trek Lives! by Jacqueline Lichtenberg, Sondra Marshak and Joan Winston (1975).