"The vigour of imagination carries it forward to invention; but understanding must always conduct it and regulate its motions. A horse of high mettle ranging at liberty, will run with great swiftness and spirit, but in an irregular track and without any fixt direction: a skilful rider makes him move straight in the road, with equal spirit and swiftness. In like manner, a fine imagination left to itself, will break out into bold sallies and wild extravagance, and overleap the bounds of truth or probability: but when it is put under the management of sound judgment, it leads to solid and useful invention, without having its natural sprightliness in the least impaired."
— Gerard, Alexander (1728-1795)
(I.iv, p. 71)
An Essay on Genius. By Alexander Gerard, D.D. Professor of Divinity in King's College, Aberdeen. (London: Printed for W. Strahan; T. Cadell, and W. Creech at Edinburgh 1774). <Link to ECCO>