Generally, it is best to not start a paper, or, in fact, any paragraph with a quotation. This is because you have provided the reader with no context. A quote needs to be in a "sandwich." Offer your idea, then add the quote as the "meat," and then explain how the quote supports your idea. Additionally, an introduction is not the best place to use any of your sources. This is the place to get the reader acquainted with your ideas. Support for your ideas belongs in the body paragraphs of an essay.
When you do use a quotation, it should always be embedded in a sentence that introduces it. For example, you might begin with "As Smith says," and then add the quotation. No quotation should ever be used on its own, as its own sentence. These are referred to as "dropped" quotes, because they feel as though they have been dropped into the essay out of the clear blue sky.