"That last alone was a triumph that proved I was right.  Male-femaleness is the greatest gift we have - romantic physical love may be unique to this planet.  I don't know.  If it is, the universe is a much poorer place than it could be... and I grok dimly that we-who-are-God will save this precious invention and spread it.  The actual joining and blending of two physical bodies with simultaneous merging of souls in shared ecstasy of love, giving and receiving and delighting in each other - well, there's nothing on Mars to touch it, and it's the source, I grok in fullness, of all that makes this planet so rich and wonderful.  And, Jubal, until a person, man or woman, has enjoyed this treasure bathed in the mutual bliss of having minds linked as closely as bodies, that person is still as virginal and alone as if he had never copulated.  But I grok that you have; your very reluctance to risk a lesser thing proves it... and, anyhow, I know it directly.  You grok.  You always have.  Without even needing the aid of the language of grokking.  Dawn told us that you were as deep into her mind as you were into her body."