Old truths must be constantly re-stated if they are not to be forgotten. To Homer, the dawn was "rosy-fingered"; to Shakespeare, it was "in russet mantle clad"; to Housman, "the ship of sunrise burning". The scientist can explain exactly why the sky looks as it does in the early morning, the physiologist why we perceive as we do. Yet no one suggests that there is no dawn at all, or that its appearance has changed over the centuries, or that any one of these percipients was mad or deceitful. Why should our knowledge of the Creator be less capable of variety and development than our knowledge of any aspect of Creation?