often used loosely (I do not say wrongly) for any of these synonyms: but I restrict it to a special sense.
"Illusion," then, is wholesome error tending to the ultimate attainment of truth; "delusion" is harmful error arising from a perverted Imagination; "hallucination" is a wandering of the Imagination, without any guidance or support of fact, involving "delusion" of the most obstinate character; "fallacy" is an error of inference or reasoning; "mistake" is the result of mal-observation or weak memory; and "error" a general name for any deviation from the truth.
Illusion, in many cases, is an exaggerative and ornative tendency of the mind. It leads the very young to think their parents perfection, and the young to think them far better and wiser than they really are; it constrains the lover to exaggerate the beauty, accomplishments, and qualities of the woman whom he loves; it tends to the distortion of history by inclining all of us to accommodate facts to the wishes and preconceptions of our idealizing nature, which is always longing for "a more ample greatness, a more exact goodness, and a more absolute variety than can be found in the nature of things";[1] and it lures us onward, young and old alike, over the rough places of life, even to the very brink of the grave, by the ever-fleeting ever-reappearing suggestions of a bright tomorrow that shall make amends for the dull and commonplace to-day.
These illusive hopes, beliefs, and aspirations are never fulfilled in this life; but even the cynic and the pessimist must acknowledge, with Francis Bacon, that they constitute the very basis of all poetry that "tends to magnanimity and morality." Those who believe in God will further recognize in illusion a divinely utilized integument for the preservation and development of aspirations that shall
- ↑ Advancement of Learning, ii. 4, 5.
