Intrinsic and extrinsic motivations are well established terms in the literature on the psychology of motivation, primarily from a set of theories called Self-Determination Theory, which was developed by Edward Deci and Richard Ryan at the University of Rochester.

FORBES: 'For the Win': How Gamification Can Transform Your Business

Willard Quine's early work was in the field of mathematical logic and set theory, the subject of half a dozen of his 23 books.

ECONOMIST: Willard Quine

Moffett set out years ago with a carefully constructed theory regarding deposition of sands in the Gulf of Mexico over many millions of years.

FORBES: Jim Bob Moffett Puts His Money Where His Mouth Is

If this theory is correct, then we have a third set of culprits for the dismal state of the economy today.

FORBES: Job Killers: A Rogues' Gallery

What does not help is that management theory about remuneration seems often to be based on a set of completely erroneous assumptions about human behaviour.

FORBES: Employee remuneration systems are often based on the wrong assumptions

On one hand they are an alternative to shares, with a pre-decided fixed income and (in theory at least) returning the full principle back at the end of a set term.

FORBES: It Started With Tulips, Now Bubble-Watchers Are Looking To The Bond Market