Lionel Trilling, The Liberal Imagination:
«In the course of one of the essays in this book I refer to a remark of John Stuart Mill’s in his famous article on Coleridge – Mill, at odds with Coleridge all down the intellectual and political line, nevertheless urged all liberals to become acquainted with this powerful conservative mind. He said that the prayer of every true partisan of liberalism should be, “ ‘Lord, enlighten thou our enemies…’; sharpen their wits, give acuteness to their perceptions and consecutiveness and clearness to their reasoning powers. We are in danger from their folly, not from their wisdom: their weakness is what fills us with apprehension, not their strength.” What Mill meant, of course, was that the intellectual pressure which an opponent like Coleridge could exert would force liberals to examine their position for its weaknesses and complacencies.
We cannot very well set about to contrive opponents who will do us the service of forcing us to become more intelligent., who will require us to keep our ideas from becoming stale, habitual, and inert. This we will have to do for ourselves. It has for some time seemed to me that a criticism which has at heart the interests of liberalism might find its most useful work not in confirming liberalism in its sense of general rightness but rather in putting under some degree of pressure the liberal ideas and assumptions of the present time. If liberalism is, as I believe it to be, a large tendency rather than a concise body of doctrine, then, as that large tendency makes itself explicit, certain of its particular expressions are bound to be relatively weaker than others, and some even useless and mistaken. If this is so, then for liberalism to be aware of the weak or wrong expressions of itself would seem to be an advantage to the tendency as a whole.»