The answer is <span>Interpretation
When creating an artwork, artists often put his emotion, principles, or pollitical value into his artwork and does not give any information about it for the audience. When the audiences see the artwork, they would combined the artform that they see with their own emotion/principles which lead to the personal interpretation on what the artists actually want to convey.
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<span> It was sparked by Stéphane Mallarmé.</span>
