Conversation starter - from Tom Harper's Thriller entitled "The Book of Secrets"

Tom Harper's Thriller entitled "The Book of Secrets"  is  an excellent read in itself but let me give you a quote worth pondering upon-a conversation comment starter from medieval section page 313

A perception of economics by a main character, the goldsmith Johannes and the money lender Soltz in the flash back sections on medieval origins of our intrigue:

"Soltz (the money lender) had it wrong about money. It is not like a plough or a pair of bellows, to be hired out and returned. It was the water driving the mill of endeavour. It did nor matter where it came from or where it went. So long as it kept flowing."

Does this still apply today, and if so to what extent: Comment welcome give your estimate on a scale say:
 0 to 100%

REFERENCE:
The Book of Secrets by Tom Harper, Thriller,
ISBN 978-0_099-53276-7
Editor, rbooks,UK