I've always thought

[Ravenpig]

That this song was Tool's reaction to all the legal problems they had with their label between Aenema and Lateralus. This song could have easily been called "Executives and lawyers". Same thing. The lyrics could easily be interpreted for something like that.

[Ghostwriter]

Maybe the parasites symbolize the executives and big business men which suck away at the band and make all the money off of them. I dunno though; I dont have much of an opinion on this song.

[joblobob]

I believe he is not only talking about lawyers and producers.

Fans are also directly pointed in this song. Some fans can be such a let down. I believe that this same message is encapsulated in Pushit(Live).

The fans are pushing and shoving him, as he tries his best...

[]v[edusa]

"The word 'politics' is derived from the word 'poly', meaning 'many', and the word 'ticks', meaning 'blood sucking parasites'."

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The ticks and leeches are anyone that are trying to change who they are to something the ticks and leeches want them to be. They are turning their blood cold and bitter.

Here is my explanation on blood, the ticks, leeches, and vampires (from my interpretation on "the patient") http://toolnavy.com/showpost.php?p=2014216&postcount=16

[jaggermeister]

hmmm.....anyone who wants more than what he's giving; living off of him.....ticks and leaches.

[miketh74]

This tune is the most intense of all Tool songs in my opinion. There must have been strong emotions behind it. Dan Carey even admitted that his weakness, if you can actually call it a weakness, are double bass songs. So, something had to have been driving them to go through with this.

Side note: As I'm sure most of you are aware, I love the fact that this song was rated the 5th best hard rock drum solo of all time. Bow to the drum god!!