On progress

Two quotations presaging the Kuhnian, from Crooked Timber (and repeated here to save the mouseclicks, but see the comments on the two posts):

Old ideas give way slowly; for they are more than abstract logical forms and categories. They are habits, predispositions, deeply engrained attitudes of aversion and preference. Moreover, the conviction persists – though history shows it to be a hallucination – that all the questions that the human mind has asked are questions that can be answered in terms of the alternativesthat the questions themselves present. But in fact intellectual progress usually occurs through sheer abandonment that results from their decreasing vitality and a change of urgent interest. We do not solve them: we get over them.
John Dewey, “The Influence of Darwinism on Philosophy” (1909).
http://crookedtimber.org/2006/04/05/who-said-it/

In a philosophical view, consistency is a certain level at all times, maintained in all the thoughts of one’s mind. But, since nature is nearly all hill and dale, how can one keep naturally advancing in knowledge without submitting to the natural inequalities in the progress? Advance into knowledge is just like advance upon the grand Erie canal, where, from the character of the country, change of level is inevitable; you are locked up and locked down with perpetual inconsistencies, and yet all the time you get on; while the dullest part of the whole route is what the boatmen call the ‘long level’ – a consistently-flat surface of sixty miles through stagnant swamps.”
Herman Melville, The Confidence-Man (1857).
http://crookedtimber.org/2006/04/05/who-said-it-part-the-second/