"Those in the ninja world who break the rules and regulations are called filth, but those who don't care about their companions... are even lower than filth."

This quote is spoken by Uchiha Obito during his confrontation with Kakashi in Naruto Shippuden. He says this to express his disillusionment with the ninja world after Rin's death and his fall into darkness. Sasuke is a common distractor as he also breaks rules, but this specific philosophy about companions being worse than filth is uniquely Obito's.