“Imagination is but a name for the free play of thought, one of the most important features of which, but still only one, is its attachment and sensibility to the memories of sight.” There is the whole root of the matter. Imagination is not a thing by itself, but a mental quality akin to physical agility, enabling the reason to act with greater velocity and certainty, intensifying faith, quickening conscience, rendering memory more vivid, sympathy more sure, judgment more certain. Every intellectual quality is intensified for good or for evil by imagination.
“There is nothing,” writes George Eliot, “more widely misleading than sagacity if it happens to get on the wrong scent; and sagacity, persuaded that men usually act and speak from distinct motives, with a consciously proposed end in view, is certain to waste its energies on imaginary game.”
Imagination, on the homœopathic principle, is the surest influence to preserve sagacity from following the scent of “imaginary game”; but it is a formidable power, imposing great risks, as well as high privilege, on its possessor. Of the former, an anecdote which occurs somewhere in Sir Walter Scott’s writings is a good illustration : —
“An Italian nobleman, suffering from ague, was inveigled by his valet into such a situation as involved a ducking and a severe fright. The valet’s intention was good — namely, to cure his master’s disease; and the cure was effectual. But his master, determined to punish him appropriately for the trick, had him tried for his life and sentenced to decapitation. He was led to the scaffold blindfolded, and laid his head on the block, when the executioner, acting on his instructions, dashed a jugful of cold water on his neck. The joke was then complete; but poor Gonella did not see it, for it was found that he had died from the shock to his nerves.”
In other words, his imagination had killed him.
(Sir Herbert Maxwell, “Imagination.” In: Meridiana: Noontide Essays. Edinburgh and London: William Blackwood and Sons, 1892, pp. 205–206).