In order to form and make up a Unity, in particular a creative Unity, the individual components must needs be of different nature, they should even be in a sense contrasts. Two homogeneous units will never be capable of forming a whole, or their whole at its best will remain barren. Man and woman become one, a physically and spiritually creative Unity, by virtue of their dissimilarity. A hook and an eye are a Unity, a fastening; but with two hooks you can do nothing. A right-hand glove with its contrast the left-hand glove makes up a whole, a pair of gloves; but two right-hand gloves you throw away. A number of perfectly similar objects do not make up a whole – a couple of cigarettes may quite well be three or nine. A quartet is a Unity because it is made up of dissimilar instruments. An orchestra is a Unity, and may be perfect as such, but twenty double-basses striking up the same tune are Chaos.

A community of but one sex would be a blind world. When in 1940 I was in Berlin, engaged by three Scandinavian papers to write about Nazi Germany, woman – and the whole world of woman – was so emphatically subdued that I might indeed have been walking about in such a one-sexed community. I felt a relief then, as I watched the young soldiers marching west, to the frontier, for in a fight the adversaries become one, and the two duellists make up a Unity.

The introduction into my life of another race, essentially different from mine, in Africa became to me a mysterious expansion of my world. My own voice and song in life there had a second set to it, and grew fuller and richer in the duet.

Within the literature of the ages one particular Unity, made up of essentially different parts, makes its appearance, disappears and again comes back: that of Master and Servant. We have met the two in rhyme, blank verse and prose, and in the varying costumes of the centuries. Here wanders the Prophet Elisha with his servant Gehazi – between whom one would have supposed the partnership to have come to an end after the affair with Naaman, but whom we meet in a later chapter apparently in the best of understanding. Here walk Terence’s Davus and Simo, and Plautus’ Calidorus and Pseudolus. Here Don Quixote rides forth, with Sancho Panza on his mule by the croup of Rosinante. Here the Fool follows King Lear across the heath in the storm and the black night, here Leporello waits in the street while inside the palazzo Don Giovanni ‘reaps his sweet reward’. Phileas Fogg struts on to the stage with one single idea in his head and versatile Passepartout at his heels. In our own streets of old Copenhagen Jeronimus and Magdelone promenade arm in arm, while behind their broad and dignified backs Henrik and Pernille make signs to one another.