Horoscope
2 of the 6 encyclopedias on this shelf carry an entry for Horoscope. Both are reproduced below, so you can see where they agree and where they differ.
Aiton's Encyclopedia (1910)
that part of the heavens, or more strictly speaking, that part of the ecliptic, which is in the eastern horizon at the instant of one's birth. The term is also applied, and more frequently, to a diagram of the heavens by means of which the astrologer was able to determine what stars were in the horizon at any particular time. He pretended to have the power to read the future of a person the hour and date of whose birth was known. In the Middle Ages astrologers were present at the birth of a prince or heir to cast the horoscope; that is, to map out and announce the influence of the planets and stars present, as it were, at his birth. That some people possessed an occult ability to consult the stars and foretell their influence was fixed in the belief of the Middle Ages, but the exercise of this supposed power has been wrapped up from time immemorial with the grossest fraud and deception. For an account of these practices the reader is referred to Scott's Quentin Durward. See also ASTROLOGER.
Collier's New Encyclopedia (1921)
in astrology, an observation of the sky and the configuration of the planets at a certain moment as at the instant of a person's birth, from which the astrologer claimed to be able to foretell the future. Also a scheme or plan of the 12 houses or 12 signs of the zodiac, in which is marked the disposition of the heavens at a particular moment, and by which astrologers pretended to be able to foretell the fortunes of persons according to the position of the stars at their birth.
What Has Changed in the Last Century
Both entries treat horoscopes as a medieval survival practised on princes and "wrapped up... with the grossest fraud and deception" — a thing of the past. Within a decade of Collier's 1921 entry it became a mass-market product: in August 1930 R. H. Naylor cast a horoscope for the newborn Princess Margaret in the Sunday Express, and the popular column of sun-sign predictions was born, now a fixture of newspapers, magazines and apps such as Co-Star. Their verdict on its validity still holds: a double-blind test by Shawn Carlson published in Nature in 1985 found astrologers could not match birth charts to personality profiles better than chance. What the old writers would not have predicted is the audience — surveys regularly find around a quarter of adults in the United States and Britain saying there is something in it.
Written for this edition, 2026.