I've come up with loads of explanations and I think this is the best one.
"Beauty is a harmonious alignment of the finest."
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Take our universe for example. The planets in it are beautiful. They're all neatly aligned by the suns gravitational pull. But yet, even though the planets are different colours - the design of the planets look harmonious together.
Take an iPad Air for example. Very few people will disagree that this product is a beautiful aesthetic design with it's shiny chamfered edges, sleek OCD alignment of the components. In fact. It will only become ugly looking when more supreme parts come out which make it's depth will look outdated. It won't be the finest anymore.
And lastly. Look at beautiful people. Although not everyone agrees with who looks beautiful. The people who are believed to be beautiful all share these common traits. Their features work in harmony with each other (for example in a guy: large nose with a strong jaw line). Their face must be neatly aligned and in proportion which in humans makes it symmetrical too. And lastly, their skin must be the finest it can be. Glowing and youthful.
I think these three rules combined can make anything beautiful. Please give me your opinion:-P thanks
Read more: Is this what beauty is?