2. Sleeping and Waking Life in Relation to the Planets

We are taught as children that the Sun is at the centre of the solar system and that the planets revolve around it-first the planet now called Mercury, then the planet now called Venus, [*In former times the names of these two planets came to be reversed. See later paragraphs of this lecture.] then the Earth plus Moon, then Mars, Jupiter and Saturn. Astronomical maps of the heavens show us where Saturn or Jupiter or Mars are to be found in certain months of the year. When we have learnt to know the relative positions of the planets at definite times of the year, we have learnt as much about the heavens as a child has learnt about the clock when from the position of the hands he is able to say that the time is half-past nine.