David Hume to Adam Smith, on the publication of Smith's The Theory of Moral Sentiments:

My Dear Mr. Smith, have patience: compose yourself to tranquillity: show yourself a philosopher in practice as well as profession: think on the emptiness and rashness and futility of the common judgments of men: how little they are regulated by reason in any subject, much more in philosophical subjects, which so far exceed the comprehension of the vulgar.

[…]

Supposing, therefore, that you have duly prepared yourself for the worst by all these reflections; I proceed to tell you the melancholy news, that your book has been very unfortunate: for the public seem disposed to applaud it extremely.

It was looked for by the foolish people with some impatience; and the mob of literati are beginning already to be very loud in its praises. Three bishops called yesterday at Millar's shop in order to buy copies, and to ask questions about the author. The Bishop of Peterborough said he had passed the evening in a company where he heard it extolled above all books in the world.

You may conclude what opinion true philosopher will entertain of it, when these retainers to superstition praise it so highly.

(via Brad DeLong)