'Knowledge rejuvenates the soul, and lightens the burden of old age. Therefore gather wisdom, that thou mayest gather sweets for thine age.'
'There is a generation of painters who, to hide their meagre knowledge, shelter themselves behind the beauty of gold and azure, and say they give not of their best because of the scanty payment they receive, and that they could surpass any man were they as well rewarded as he. O fools! what hinders them to make something beautiful, and to say, "This picture is such a price, and this other is less, and this, third least of all; showing that they have work for every price?"'
'Not infrequently the lust for gold brings even the good masters down to the level of craftsmen. Thus my countryman and comrade, Perugino the Florentine, arrived at such rapidity of execution, that once he replied to his wife, who called him to dinner, "Serve the soup while I paint one more saint!"'
'The artist who has no mistrust of himself will never attain to the supreme heights of art. Well for thee if thy work be higher, ill for thee if it equal, woe to thee if it fall below, thine own estimation! Pitiful is that artificer who, persuaded that he has produced a masterpiece, questions wonderingly how God can have helped him to such purpose.'
'Listen with long suffering to the criticisms which men pass on your picture; and weigh their words to see if, perchance, they, faulting it, be in the right. If they be right, correct; if they be wrong, feign deafness; or if they be persons worthy of notice, show them their error. The judgment of an enemy is often nearer the truth than the judgment of a friend; hatred is often profounder than love. The intellect of him who hates, sees and penetrates better than the intellect of him who loves. A true friend is like thyself; but an enemy resembles thee not, and in this is his strength. Hatred throws light. Remember this, and despise not the criticisms of thine enemy.'