Quartet conditions are unbalanced. They only apply to Pals. No condition is asked from the occupier Israel, which is not logic. Pals have experience with reconizing Israel in 1988: till present Israel refuses to recognize a Pal state. So it is logic that Hamas refuses to recognize Israel at this stage (they many times said to accept a negotiated solution agreed in a referendum). Demanding ceding all violence is against international law which recognises the right a an occupied people to use this as last resort if other means fail. Recognizing all previous agreements is not logic since Israel constantly acts against them (with settlements, blokkade of Gaza, etc etc.). . . .
from the article: Hamas, Fatah leaders meet in Cairo for Palestinian unity talks