"The relationship between thinking and walking is grained deep into language history, illuminated by perhaps the most wonderful etymology I know. The trail begins with our verb to learn, meaning 'to acquire knowledge'.
Moving backwards in language time, we reach the Old English leornian, 'to get knowledge, to be cultivated'.
From leornian the path leads further back, into the fricative thickets of Proto-Germanic, and to the word liznojan, which has a base sense of 'to follow or to find a track' (from the Proto-Indo-European prefix leis-, meaning 'track').
'To learn' therefore means at root – at route – 'to follow a track'. Who knew? Not I, and I am grateful to the etymologist-explorers who uncovered those lost trails connecting 'learning' with 'path-following'."
A London Walk costs £9 – £7 concession. To join a London Walk, simply meet your guide at the designated tube station at the appointed time. Details of all London Walks can be found at www.walks.com.