Once again, it seems the irrefutable wisdom of “if it’s not Scottish, it’s crap” has been confirmed. Iain Murray writes:

Chaps,
It’s my understanding that Jefferson took the concept from Scottish philosopher Lord Kames, whose work Principles of Morality in National Religion included the passage, “People have an innate sense of right and wrong. When they act virtuously, they increase the general happiness of mankind. Thus, the pursuit of virtue and morality is the pursuit of happiness.” My notes tell me Jefferson underlined this passage.
So Andrew is wrong, again, it seems…
Iain