Page 15. " western spiral arm "

The Milky Way, as our galaxy is known, has two major and several minor spiral arms, as shown in the image below.

Page 15. " ape-descended life forms "

A reference to Charles Darwin's theory of evolution, which posits that humans are descended from apes.

     

Page 15. " two thousand years after one man had been nailed to a tree "

Adams refers to Jesus of Nazareth, the central Christian religious figure whose message was somewhat more complicated than everyone just being nicer to each other.  Adams himself was not religious, describing himself as a “radical atheist”, although he was fascinated by religion due to its huge influence on human history.

Read an interview with Adams focusing on his atheism and attitudes to religion.

Page 15. " a small cafe in Rickmansworth "
rickmansworth
Creative Commons Attributionrickmansworth - Credit: NIGEL COX

Rickmansworth is an unremarkable home counties town just outside London. Describing a character suddenly discovering the meaning of life, the universe and everything in an unremarkable café in an unexceptional town is a juxtaposition of the prosaic with the extraordinary that is typical of Adam's writing style.

Google Map
Page 15. " a book called The Hitchhiker's Guide to the Galaxy "

In 1992 Douglas Adams founded the h2g2 website as a kind of online version of the Hitchhiker's Guide, "an unconventional guide to life, the universe and everything". Of course this could also be a definition of Wikipedia, making us all Ford Prefects, travelling the world (if not the universe) to update the 'guide'.

i phone
Creative Commons Attribution Share AlikeiPhone - Credit: Renato Mitra

It is also worth pondering what Douglas Adams, a life-long Mac lover and gadget fan, would have made of the iPhone.

Eoin Colfer, author of the Artemis Fowl series and the official The Hitchhiker's Guide sequel And Another Thing..., commented  “I think the Hitchhiker’s Guide basically was the iPhone. Adams even described the guide as a small black gadget with a touch button."

Page 18. " descendant of Genghis Khan "

Genghis Khan was the founder and ruler of the Mongol empire in the twelfth and early thirteen centuries, and was proverbially a despotic ruler and bloodthirsty warrior.

Page 21. " a small planet in the vicinity of Betelgeuse "

Comparing the very ordinary town of Guildford with a planet somewhere near Betelgeuse is classic Adams technique.  Guildford is a large town in Surrey, a county in southern England.  Betelgeuse is one of the brightest stars visible from earth, located around 640 lightyears away.

guildford
Public DomainGuildford - Credit: S Knights

 

Page 21. " the name Ford Prefect "

Ford Prefect
GNU Free Documentation LicenseFord Prefect - Credit: Charles 01
Ford Prefect's choice of pseudonym is one joke that has somewhat dated. It was the name of a line of cars manufactured in Britain by the Ford Motor Company from the 1930s until the early 1960s.

 

 

Page 21. " less than thirty Altairan dollars a day "

This is a reference to Arthur Frommer’s seminal 1957 travel guide Europe on 5 Dollars a Day.  The book was highly influential in changing attitudes to foreign travel among Americans.  It laid the foundations for Frommer’s guide book business as well as backpacker orientated guide books like the Rough Guide and Lonely Planet series.

Page 25. " take it as read that he's actually here "

A variation on George Berkeley's theory of immaterialism or subjective idealism: "esse est percipi" (to be is to be perceived).

In his work A Treatise Concerning the Principles of Human Knowledge Berkeley posits the idea that "surely there is nothing easier than for me to imagine trees, for instance, in a park and nobody by to perceive them. The objects of sense exist only when they are perceived; the trees therefore are in the garden no longer than while there is somebody by to perceive them."

This is more often rendered as the hypothetical question: "if a tree falls in an empty forest with no one present to witness it, did it really make a sound?"