This "aphorism" was expressed in different forms by Josh Billings and Socrates. note: Often misquoted as, "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge," and often misattributed to Stephen Hawking. 
Source: Cleopatra's Nose: Essays on the Unexpected (1995). 
                                    
“Progress is a fact. Even so, faith in progress is a superstition. Science enables humans to satisfy their needs. It does nothing to change them. They are no different today from what they have always been. There is progress in knowledge, but not in ethics. This is the verdict both of science and history, and the view of every one of the world's religions. The growth of knowledge is real and - barring a worldwide catastrophe - it is now irreversible. Improvements in government and society are no less real, but they are temporary. Not only can they be lost, they are sure to be. History is not progress or decline, but recurring gain and loss. The advance of knowledge deludes us into thinking we are different from other animals, but our history shows that we are not.”
            Non-Progress: De Quincey's Toothache (p. 155) 
Straw Dogs: Thoughts on Humans and Other Animals (2002)
        
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John Gray 164
British philosopher 1948Related quotes
                                        
                                        Sweet Morality (p. 235) 
The Immortalization Commission: The Strange Quest to Cheat Death (2011)
                                    
As quoted in Humphry Davy : Science & Power (1998) by David Knight, p. 87
Speech (October 1927); quoted in Atatürk’ten Düşünceler by E. Z. Karal, p. 59
                                        
                                        Part I : Contemporary Issues in Science, Ch. 1 : "The Scientist as Rebel" 
The Scientist As Rebel (2006) 
Context: The progress of science requires the growth of understanding in both directions, downward from the whole to the parts and upward from the parts to the whole. A reductionist philosophy, arbitrarily proclaiming that the growth of understanding must go only in one direction, makes no scientific sense. Indeed, dogmatic philosophical beliefs of any kind have no place in science.
                                    
                                        
                                        Encyclical Letter Spe Salvi of the Supreme Pontiff Benedict XVI to the Bishops Priests and Deacons Men and Women Religious and All the Lay Faithful On Christian Hope, 30 November 2007 
2007
                                    
                                        
                                        1950s, Rediscovering Lost Values (1954) 
Context: There is something wrong with our world, something fundamentally and basically wrong. I don't think we have to look too far to see that. I'm sure that most of you would agree with me in making that assertion. And when we stop to analyze the cause of our world's ills, many things come to mind. We begin to wonder if it is due to the fact that we don't know enough. But it can't be that. Because in terms of accumulated knowledge we know more today than men have known in any period of human history. We have the facts at our disposal. We know more about mathematics, about science, about social science, and philosophy than we've ever known in any period of the world's history. So it can't be because we don't know enough. And then we wonder if it is due to the fact that our scientific genius lags behind. That is, if we have not made enough progress scientifically. Well then, it can't be that. For our scientific progress over the past years has been amazing. Man through his scientific genius has been able to dwarf distance and place time in chains, so that today it's possible to eat breakfast in New York City and supper in London, England. Back in about 1753 it took a letter three days to go from New York City to Washington, and today you can go from here to China in less time than that. It can't be because man is stagnant in his scientific progress. Man's scientific genius has been amazing. I think we have to look much deeper than that if we are to find the real cause of man's problems and the real cause of the world's ills today. If we are to really find it I think we will have to look in the hearts and souls of men.
                                    
                                        
                                        "Why We Remain Jews" (1962) 
Context: Science, as the positivist understands it, is susceptible of infinite progress. That you learn in every elementary school today, I believe. Every result of science is provisional and subject to future revision, and this will never change. In other words, fifty thousand years from now there will still be results entirely different from those now, but still subject to revision. Science is susceptible of infinite progress. But how can science be susceptible of infinite progress if its object does not have an inner infinity? The belief admitted by all believers in science today — that science is by its nature essentially progressive, and eternally progressive — implies, without saying it, that being is mysterious. And here is the point where the two lines I have tried to trace do not meet exactly, but where they come within hailing distance. And, I believe, to expect more in a general way, of people in general, would be unreasonable.