The idea that with knowledge comes grief is true as well as false in so many ways. The more knowledgeable someone is, the more capable of being distraught from all of the troubles of the world they are. When someone is ignorant, they are oblivious to their surroundings and are happier because they have no idea of all of the bad things going on in the world. There are arguments to defend both sides, some would rather be wise even though it means it would cause them grief and others would rather be ignorant and unaware of any troubles.
The Buddhists believe to reach nirvana, one must attain as much knowledge as possible. Nirvana is absolute happiness, therefore their beliefs are contrary to "With knowledge comes grief". Despite the fact that the more intelligent you become, the more aware of your depressing surroundings you become as well, some would rather live a life rich in wisdom while others would rather live in a smaller world, unconscious to any problems they might have if they were not so ignorant. A person's world grows larger with less boundaries the more intelligent they become and they can constantly learn new things. The pursuit of knowledge is a never ending journey, so life never becomes dull because there is always something new to be learned. This, while being a positive to life, is also a negative because no matter how much you learn, it is impossible to know everything therefore very frustrating instead of being satisfied with knowing nothing and just be happy in life.
.
"Ignorance is bliss" is very true in many ways. The less someone knows about their troubles, the less they can bother them. In a way it is like the quote, "What you don't know can't hurt you". Something that you do not know anything about cannot disturb you because it does not even exist in your mind. For example, if your pet and you do not find out because your parents buy you a new one that looks exactly like the old one, you are unaffected and still happy because you are completely ignorant to the situation.