What is the philosophical view of believing that ignorance is bliss, or that knowledge of yourself or the world is bad for you?
There are a couple avenues of research here:
1) rational ignorance theory- the idea that sometimes the effort required to gain knowledge is not worth the benefit the knowledge would bring
2) original sin and other ideas from the religious field related to impairment of the spirit by knowledge and to obtaining some form of spiritual success through various practices other than obtaining knowledge. There are Mystics, Sufis, Zen Buddhists and others in this vein.
These may not make negative moral statements about knowledge, but their moral force does not operate through knowledge or give rationality the pride of place.
For example, see M. Foucault "Security, Territory, Population: Lectures at the Collège de France 1977--1978" pp212-213 LINK
"In mysticism ignorance is knowing and knowledge has the very form of ignorance."
There is something of this gist in ancient philosophy, namely The Writings of Chuang Tzu:
... if an end were put to sageness and wisdom put away, the great robbers would cease to arise. If jade were put away and pearls broken to bits, the small thieves would not appear. If tallies were burned and seals broken in pieces, the people would become simple and unsophisticated.
... the common people are perplexed by all the sophistry. Hence there is great disorder continually in the world, and the guilt of it is due to that fondness for knowledge. Thus it is that all men know to seek for the knowledge that they have not attained to; and do not know to seek for that which they already have (in themselves); and that they know to condemn what they do not approve (in others), and do not know to condemn what they have allowed in themselves;-- it is this which occasions the great confusion and disorder.
Incidentally, the first line on the page elucidates a certain chapter of the The Tâo Te Ching:
Fishes should not be taken from the deep; instruments for the profit of a state should not be shown to the people.
* Alternative link with notes: Khü Khieh, or 'Cutting open Satchels'
There is a similar sentiment on the problem of knowledge in Buddhism, dating from around the same time, circa 6th century BCE:
Abandoning (the views) he had (previously) held and not taking up (another), he does not seek a support even in knowledge. Among those who dispute he is certainly not one to take sides. He does not [have] recourse to a view at all. In whom there is no inclination to either extreme, for becoming or non-becoming, here or in another existence, for him there does not exist a fixed viewpoint on investigating the doctrines assumed (by others). Concerning the seen, the heard and the cognized he does not form the least notion. That brahmana who does not grasp at a view, with what could he be identified in the world?
I am approaching this question with two types of people in mind. I do realize there are infinite types of people in the finest levels but for now i am focusing on two. the two are the ones who do know they don't know or philosophers and the ones who don't know that they don't know. its obvious witch one is blissful in ignorance. the one who gains bliss from knowing is the philosopher.