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labor under the illusion of/that

To live, operate, or function with the unyielding belief in something, especially that which is fanciful, unrealistic, or untrue. Primarily heard in US. Jeremy's always labored under the illusion of being a great writer, even though he's never written more than a few crummy poems. No one likes paying taxes, but those who would call for them to be done away with altogether are laboring under the illusion that our society can function without them!
See also: illusion, labor, of, that

be under no illusion

To know and understand the reality or truth of a situation. Don't worry, I'm not getting back together with Alex. After all his lies, I'm under no illusion about how he operates.
See also: illusion, no

be under the illusion that

To be living, operating, or functioning based on a belief that is fanciful, unrealistic, or untrue. Jeremy's always been under the illusion that he's a great writer, even though he's never written more than a few crummy poems. No one likes paying taxes, but those who would call for them to be done away with altogether are under the illusion that our society can function without them.
See also: illusion, that

be under the illusion that

wrongly believe that.
1998 Independent The keening harmonies of the Brothers Gibb, a million naff dance routines by medallion men under the illusion that they were John Travolta.
See also: illusion, that

be under no illusion (or illusions)

be fully aware of the true state of affairs.
1992 Christian Scientist Monitor It is crucial to the nation's security…that we be under no illusions about reasons for this zero-loss rate.
See also: illusion, no
References in periodicals archive ?
The harder people found the task, the more the illusion helped them," he added.
Sanjiv Sethi (@EyeManSonny) August 8, 2017 Skye explained: "In my version of the famous Cafe-Wall illusion, I have mixed together both the original CafAaAaAeA@-Wall illusion that was made famous by Richard Grego - and which showcases the brickwork laid on the wall of a cafe in Bristol, England - with the work of Akiyoshi Kitaoka, who has developed a number of different versions using the same underlying effect.
presents Intimate Illusions performing 7 shows set in the hip W Boston Hotel ballroom offering a truly memorable experience during your Boston night on the town.
Spread across the entire rooftop of the Marsa Malaz Kempinski in Qatar, the space was designed by Creative Clinic, and the interiors at Illusion combine both vintage and modern aesthetics.
Lowry's original painting shows bent figures in front of an industrial landscape, but the illusion sees the figures seemingly start to shuffle along.
has entered the fragrance category with Lasting Illusions, a line of fragrance mists for men and women that combine value and luxury.
Earlier studies of the "Rotating Snakes" indicated the perception of motion was triggered by the eyes moving slowly across the illusion.
Let's look at some of the tricks our brains are subject to on even clear days, when such an illusion or dispute between eyes and brain when presented with a sloping runway can prompt us to negatively alter our descent.
The effect of this illusion in real-life is illustrated by the now-classic example of using a cellular phone while driving.
Illusion creates on-shelf excitement, through deep, rich application of opaque, metallized or transparent colors, as well as laser decoration, on internal product surfaces.
I suggest that the intention to create illusion is no more than a rhetoric device to persuade an audience that they are watching a truthful fictional world, with neither necessity nor ability to materialize it.
French thinker Baudrillard (1929-2007) reports the murder of reality and the extermination of an illusion--and not just any illusion, but the vital illusion, the radical illusion of the world.
Taking a good, long look at the reality of it all, "The Illusion of Entrepreneurship : The Costly Myths That Entrepreneurs, Investors, and Policy Makers Live By" takes into account the industries that are popular for start up, how they are financed, the characteristics of an entrepreneur, and strategies for new businesses to survive when they first start.
R]" The Art and Vision: Seeing in 3-D[R] workbook describes how artists create the illusion of three-dimensions by exploring the basic concepts of vision, size scaling, overlapping, atmospheric perspective and linear perspective.
We wanted to show the trajectory of the son's journey in the production's design, from the first illusion, a world of softness and romance, where love seems to offer all answers--which you see in the warm amber colors and the joyfulness of the image on the right--to the third illusion, the cold, harsh world on the left, where you see the structure of the clothes and umbrellas but nothing else, and the wind blows right through the characters.