Caution: Students may use Wikipedia for ideas and referrals to scholarly sources but probably will seldom actually cite Wikipedia.
If nine of every 10 authors you read conclude that Nietzsche was a "prophet of modernity," then this is a possible source for a thesis statement.
Your paper could explain why Nietzsche was prophetic in his assessment of the modern condition. Begin with an introductory paragraph that summarizes the rest of your work.
Avoid using personal pronouns such as "I" or "we," in order to make your work seem more scholarly in its tone.
The introduction should contain your thesis stated clearly and precisely.