I can agree with this, as long as you are exploring the concept in a different manner (in other words, adding originality). If you find that your story is too similar to those of others, I recommend checking out TV Tropes (http://tvtropes.org/pmwiki/pmwiki.php/Main/HomePage) for some interesting ways of mixing things up.
Yes, because browsing an index of other people's ideas is a great way to be original. It's impossible to make this not sound sarcastic, but really, it's not.
For one, tropers have the habit of writing 'Playing With' pages where they document every possible use of a trope even if it's never actually been used in anything. For another, every possible spelling of every possible chord has probably been written down in some music book, yet music is still original because of the near-infinite ways of combining chords, and the meanings imbued in every work by its composer. Even further, it's easy to have ideas, but at birth they are only dilute semblances of what they may be. Some of this potential may be realised in reflection, some through experimentation, and some by constraints. But ideas crystallize in no more palpable way than when reading another's words, and finding them already within one's own heart.
I don't feel that originality -- being different from others -- is the important thing in art. Most of the best works ever created in any medium are mere developments on established genres and tropes. And trying to be different for the sake of being different leads one into pointless obfuscations and cliched artiness. Rather, I support originality in the sense that the origin of one's work is one's own artistic sense, regardless whether other people have thought similarly. People know what cliches they are tired of, and what tropes they feel are unfairly scarce. To avoid the former and to seek the latter is sufficient for artistry, provided it is done with due reflection and earnestness.
