"Knowledge is both a gift and a curse". Thar's my reasoning. Most knowledge is good knowledge; you know something and you are more enlightened from it. The bad knowledge is the stuff that affects you and others. I believe the recent movie "Hereafter" is a pretty good explanation. Sometimes, you just need to let things go as they are and not know the full circumstances, as it could hurt you.
Knowledge is a burden, just think about it. As you get older, knowledge makes the world shrink and turns you into a far more analytical person, taking away innocence and ignorance, both of which are bliss. Everything seems better when you're a clueless kid because it's harder to be critical without knowledge. The world also gets a little darker the more knowledge you get because most of knowledge is laced with lessons on aspects of human nature, many of which are evil. It all depends on what kind of knowledge I guess, because learning subjects like math or astronomy isn't going to rob you of anything except maybe detract from the magic of the unknown which so excites us as kids.
It really is a gift as well as a curse. If you knew alot about a certain bad subject, and did nothing about it, it is a burden. But to have further knowledge about that bad subject, and be able to make the bad subject good, then it is a great thing. So..... Yeah.
You can't just say "knowledge is a burden". There are different types of knowledge. If anyone told me that my knowledge is a burden I would laugh him out. I know so many good things and also necessary things, why should this be a burden. If you know that someone's gonna kill you than knowledge is a burden.
Knowledge is power and power corrupts. I'd say that while it's possible for knowledge to be a burden - using knowledge for the right reasons lessens that burden.
Knowledge is a necessary evil. Without knowledge we are lost, but with knowledge we put the world at risk with dangerous things. As Einstein said, "Technological progress is like an axe in the hands of a pathological criminal."
There is both good and bad knowledge. One of my aunts recently had jury duty on a murder case, she did not want too see the pictures of someones head bashed in, she is still having nightmares about those pictures.