Definition: An illusion is something that appears real, but isn’t. Magicians use illusion to convince us that we see something they want us to see, such as a person being cut in half.
From a personal development standpoint though, it is important to realize the difficulty in separating reality from illusion. Much of what we recall from past events is illusion because our brains don’t hold an entire video of the actual experience, only the highlights.
Spiritualists tell us that all life is an illusion created to allow us to experience separation from God and each other. Did you ever have a vivid dream, only to awake in disbelief that it was a dream and not “real?”
Example: David Copperfield’s magical act of making huge buildings disappear is an illusion.