This week's First Impressions, the competition in which you have to identify a book from its opening line, comes from a journalist fascinated by Copernicus: "We can add to our knowledge, but we cannot subtract from it."
Entries should be submitted to First Impressions, The THES, Admiral House, 66-68 East Smithfield, London E1 9XY, faxed to 0171 782 3300 or emailed to theschat@thes.co.uk
The winner receives a Pounds 20 book token and the closing date is July 15.
The winner of last week's competition, who correctly identified Stendhal's The Charterhouse of Parma, is Oliver Moore of London.