Political dialogues.

The dialogues which appear in this book were all originally written for broadcasting. The wireless, or ‘sound radio', lends itself readily to this literary genre, for the ear, which tires of hearing a single voice for any length of time, feasts on variety. And when the ear demands a change of sound, the mind demands a change of standpoint; a relay of voices uttering successive parts of a single discourse would be worse than a monologue. What the listener can best appreciate is a conversation, a discussion, a debate, provided the speeches are not too long, or an argument, if it is a measured one and not a battle of passions; a 'battle of wits', perhaps, if the military metaphor is not misleading; at any rate, a dialectical exchange of antithetical opinions and perspectives.
The dialogue is also a form of writing which has been favoured by philosophers. Plato, for example, and Hume and Berkeley exploited the form with notable success. Assuredly these three are not mere technical philosophers, but men of letters, each commanding a distinctive style of his own; and yet the secret of their success may lie in the very nature of the subject. Plato said that philosophy is a kind of dialogue of the soul with itself. And those modern philosophers who see philosophy as the province of 'dialectical reason' can hardly be said to disagree with him. So the dialogue form seems to be a natural manner in which philosophical ideas can be articulated and explored.