Were it possible to trace the succession of ideas in the mind of Sir Isaac Newton, during the time that he made his greatest discoveries, I make no doubt but our amazement at the extent of his genius would a little subside. But if, when a man publishes his discoveries, he either through a design, or through habit, omit the intermediary steps by which he himself arrived at them, it is no wonder that his speculations confound them, and that the generality of mankind stand amazed at his reach of thought. If a man ascend to the top of a building by the help of a common ladder, but cut away most of the steps after he has done with them, leaving only every ninth of tenth step, the view of the ladder, in the condition which he has pleased to exhibit it, gives us a prodigious, but unjust view of the man who could have made use of it. But if he had intended that any body should follow him, he should have left the ladder as he constructed it, or perhaps as he found it, for it might have been a mere accident that threw it in his way... I think that the interests of science have suffered by the excessive admiration and wonder with which several first rate philosophers are considered, and that an opinion of the greater equality of mankind, in point of genius, and power of understanding, would be of real service in the present age." - Joseph Priestly, The History and present State of Electricity

The section where I've added an ellipsis is a section where he discusses Newton in more detail. That entire part of the text is worth reading. Priestly wrote the book before he did his work on the composition of air. The book is, as far as I am aware, the first attempt at actual history of science. (I'm meaning to read the whole thing at some point, but the occasionally archaic grammar makes for slow reading.)