20. While, therefore, in these and such other directions, I shall endeavour to put every adequate means of advance within reach of the members of my class, I shall use my own best energy to show them what is consummately beautiful and well done, by men who have passed through the symbolic or suggestive stage of design, and have enabled themselves to comply, by truth of representation, with the strictest or most eager demands of accurate science, and of disciplined passion. I shall therefore direct your observation, during the greater part of the time you may spare to me, to what is indisputably best, both in painting and sculpture; trusting that you will afterwards recognise the nascent and partial skill of former days both with greater interest and greater respect, when you know the full difficulty of what it attempted, and the complete range of what it foretold.