Laughter arises from the view of two or more inconsistent, unsuitable, or incongruous parts or circumstances, considered as united in one complex object or assemblage, or as acquiring a sort of mutual relation from the peculiar manner in which the mind takes notice of them.
And I thought, "Hey, that sounds really familiar." So I followed the footnote to the citation:
Beattie, J. (1776) . An essay on laughter, and ludicrous composition. In Essays. William Creech, Edinburgh, Reprinted by Garland, New York, 1971. Quoted in Raskin, V. (1985). Semantic Mechanisms of Humour. Reidel, Dordrecht, 1985.
Way to go, Beattie! I've read the work in question (it develops some ideas of Hutcheson). I find I never posted any passages from the work in question on Siris, although I thought I had; but it gives me a chance to link to other things I've posted on Beattie. You can go here for Beattie on association of ideas (from another of the essays, on memory and imagination), here on political liberty and genius, here on taste, here on moral problems with determinism. Here is a note on his taxonomy of evidentness.
A brief passage that touches on one theme Hutcheson develops in his (brief) account of laughter can be found here.
In any case, it always warms my heart to see that someone has been reading something of Beattie's and found it useful.
(At HL, here's an old post with just some online resources on Beattie.)