He is the lead singer of Tool. Keenan is ranked with Marilyn Manson in terms of musical talent, ability to write and perform music successfully, and to the untrained eye and ear, creepiness. If anyone needs any proof that James Maynard Keenan is a genius, simply listen to these songs:
Wings For Marie
10,000 Days (Wings pt 2)
But most importantly:
Lateralus was written in an unusual way. It was written so that the lyrics begin at 1 minute 38 seconds. This is equal to what is known as the Golden Ratio, which is 1.618. It is the most pleasing number to the human eye and has been seen in nature. The lyrics follow the Fibbonacci Sequence, which has also been seen in nature, although it is not certain why.