"It's easy to fool the eye but it's hard to fool the heart." This is a quote by Al Pacino. In the movie, The Godfather (1972), Pacino as Michael Corleone uses this line. He is telling us that it is good to trust your heart. If you feel that something is wrong, it probably is wrong. You don't need to explain your feeling.

The direct situation in the movie with Michael Corleone is about the emotion that he is feeling. He sees the purity of another's intentions. His eyes are seeing things that are actual, and even those things that appear actual. Example: to all appearances, he is attentive to his wife, but she 'feels' a change in their relationship. It is not the same to her. She believes that he has fallen out of love with her, or is cheating on her, or both.

Her "heart," a metaphor for love, feelings and emotion, knows that something is wrong; it can't be fooled.

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