The only revolutions wh[ich] have turned out well have been defensive revolutions – ours of 1688 – the French of 1830 – the American was, to a great extent, of the same kind.
Source, in full
Journal entry (29 December [1858]), quoted in Joseph Hamburger, 'Introduction', to Thomas Babington Macaulay, Napoleon and the Restoration of the Bourbons: The Completed Portion of Macaulay's Projected "History of France from the Restoration of the Bourbons to the Accession of Louis Philippe", ed. Joseph Hamburger (1977), p. 22