With far greater thoroughness and completeness does thought act upon the mind: thought blends with thought with a force and subtleness unknown in matter. Watch the principle in action. Let any man habitually read good books--and by good books I mean the production of any person whose mind is illumined by faith and whose heart is fed by the sacraments--it matters little in what shape such books reach us, let it be a novel or a book of poems or essays. No man can invariably read such works without growing imperceptibly better. His Catholic principles grow more robust; he becomes more fearless in expressing them; each volume leaves an aroma behind and imparts a new flavour to his life. Fresh oil is poured into the lamp of his piety, its flame burns brighter, he feels an unction in his prayers; he has a holy relish for the sacraments. His very interests in life change: he looks on everything with supernatural eyes, he becomes touchy about the interests of the Church, anxious about the foreign missions, and feels an insult to the Holy See as a wound. The food his brain is living on is leavening his whole life, giving colour, tone and trend to his existence. [Side note: Brownson] This literature, on which he nourishes himself, has been admirably described by the mastermind of Catholic America--Dr. Brownson:--"Catholic literature is robust and healthy of a ruddy complexion, and full of life. It knows no sadness but the sadness of sin, and it rejoices for evermore. It eschews melancholy as the devil's best friend on earth, abhors the morbid sentimentality which feeds upon itself and grows by what it feeds upon. . . . It washes its face, anoints its head, puts on its festive robe, goes forth into the fresh air, the bright sunshine; and, when occasion requires, rings out the merry laugh that does one's heart good to hear. It is on principle that the Catholic approves such gladsome and smiling literature."[1] [1] Vol. xix., p. 155. Now look at the converse picture. Let the mind of the most devout Catholic feed on the writings of the Protestant or sensualist and mark the transformation. See how his soul becomes enervated, his judgment warped and his heart invaded by every temptation. His Catholic principles insensibly vanish, and the standards of paganism replace them. The light of the supernatural dies in his eyes, a film of clay overspreads his vision; he looks on the Church through coloured lenses, and the rankness of earth is upon his life. Thus our thoughts, views and actions are marvellously coloured and influenced by the books we read. [Side note: The English press operating on the Irish mind] Let us now turn to examine how this bears on our own lives and the lives of those around us.