What is the best song ever written?

Well I can already see this question causing endless debate and fierce arguments. Well in my personal and always valued opinion I would have to say from a lyrical stand point either 10,000 days by Tool or almost any RAtM song. My favorite song however would either be Cemetary Gates by Pantera or anything made off the album Master of Puppets by Metallica or the album Seasons in the Abyss by Slayer. You know what this question is to hard, I like too may bands so it's a tie between almost anything made by Slayer, Pantera, Metallica, Megadeth, Trivium, Tool, Avenged Sevenfold, In Flames, Sabbath, Dio, Rage Against the Machine, Shadows Fall, Smashing Pumpkins... There's a lot more but I'm failing to mention but unfortunately due to time constraints that's all I have at this point.