I would suggest that:
1 - Epicurus anticipated the need to say this by about 2000 years,
2 - That the need to say it was planted firmly at least as far back as Plato, and by every Greek philosopher before and after who rejected the senses as the ultimate source of all reliable source of information, and
3 - Orwell was right and in league with Epicurus in identifying lack of confidence in the senses as the ultimate weapon of those who consider themselves "the golden" elite:
The Party told you to reject the evidence of your eyes and ears. It was their final, most essential command. His heart sank as he thought of the enormous power arrayed against him, the ease with which any Party intellectual would overthrow him in debate, the subtle arguments which he would not be able to understand, much less answer. And yet he was in the right! They were wrong and he was right. The obvious, the silly, and the true had got to be defended. Truisms are true, hold on to that! The solid world exists, its laws do not change. Stones are hard, water is wet, objects unsupported fall toward the earth's center.
With the feeling that he was speaking to O'Brien, and also that he was setting forth an important axiom, he wrote:
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
(I know nothing about that page except that it came up first in my googling for a well-formatted copy.)