My name is Danielle Dombrowski, I am in the 7th grade and my teacher gave us a riddle to figure out which mathemtician we would have to do a report on. The only problem is that I don't know what the answer is. Can you help? The riddle is

"This 16th century mathematician, having predicted the day of his death, took poison to make sure it came true. Who is it?"

Hope that you can help. Thanks.

I looked at The MacTutor History of Mathematics archive in the Biographies Index for 1500-1599. There is a note there on Jerome Cardan (Girolamo Cardano). Near the end of this note is the sentance "Cardan is reported to have correctly predicted the exact date of his own death but it has been claimed that he achieved this by committing suicide."