"Youth is the most important thing in the world"

In the book The picture of Dorian Gray, there is this sentence. Youth is the most important thing 

in the world,  he want be young always, for he can enjoy of his beauty.

Some people do everything to seem young, because don't accept to grow old. 

I think that youth isn't most important thing. When one person is happy and people feel good. 

The most important thing is the soul. Perhaps we must laugh in life. We learn to value the soul of 

people and we are happy and enjoy the life.