Are there any definitions for the following three terms that are widely agreed upon in economics?
In particular, are these terms identical? If not, what differentiates them?
I have noticed that 19th-century writings contain a great deal of discussion and disagreements on what these terms mean.
In contrast, in modern economics, there seems to be little discussion or debate on what these terms mean. To me, this suggests two possibilities: (a) there is consensus on what these terms mean; or (b) there is no consensus on what these terms mean but economists use them freely anyway.