Liam was sucking his thumb a number of weeks ago and I kept replacing it with his pacifier because I too believe breaking him of a pacifier will be easier than a thumb. Well, we have those Soothie pacifiers that they give you in the hospital and he's discovered sticking his thumb in the hole so he's actually sucking his thumb and pacifier. His most recent discovery is sucking his fingers. He'll only suck the left hand though. He gets so mad when I take his fingers out of his mouth now.