The fact that significant form was the only common quality in the works that moved me, and that in the works that moved me most and seemed most to move the most sensitive people—­in primitive art, that is to say—­it was almost the only quality, had led me to my hypothesis before ever I became familiar with the works of Cezanne and his followers.  Cezanne carried me off my feet before ever I noticed that his strongest characteristic was an insistence on the supremacy of significant form.  When I noticed this, my admiration for Cezanne and some of his followers confirmed me in my aesthetic theories.  Naturally I had found no difficulty in liking them since I found in them exactly what I liked in everything else that moved me.

There is no mystery about Post-Impressionism; a good Post-Impressionist picture is good for precisely the same reasons that any other picture is good.  The essential quality in art is permanent.  Post-Impressionism, therefore, implies no violent break with the past.  It is merely a deliberate rejection of certain hampering traditions of modern growth.  It does deny that art need ever take orders from the past; but that is not a badge of Post-Impressionism, it is the commonest mark of vitality.  Even to speak of Post-Impressionism as a movement may lead to misconceptions; the habit of speaking of movements at all is rather misleading.  The stream of art has never run utterly dry:  it flows through the ages, now broad now narrow, now deep now shallow, now rapid now sluggish:  its colour is changing always.  But who can set a mark against the exact point of change?  In the earlier nineteenth century the stream ran very low.  In the days of the Impressionists, against whom the contemporary movement is in some ways a reaction, it had already become copious.  Any attempt to dam and imprison this river, to choose out a particular school or movement and say:  “Here art begins and there it ends,” is a pernicious absurdity.  That way Academization lies.  At this moment there are not above half a dozen good painters alive who do not derive, to some extent, from Cezanne, and belong, in some sense, to the Post-Impressionist movement; but tomorrow a great painter may arise who will create significant form by means superficially opposed to those of Cezanne.  Superficially, I say, because, essentially, all good art is of the same movement:  there are only two kinds of art, good and bad.  Nevertheless, the division of the stream into reaches, distinguished by differences of manner, is intelligible and, to historians at any rate, useful.  The reaches also differ from each other in volume; one period of art is distinguished from another by its fertility.  For a few fortunate years or decades the output of considerable art is great.  Suddenly it ceases; or slowly it dwindles:  a movement has exhausted itself.  How far a movement is made by the fortuitous synchronisation of a number of good artists, and how far the artists are helped to the creation of significant