The Secret Garden: [In the Garden]
"in each century since the beginning of the world wonderful things have been discovered. in the last century more amazing things were found out than in any century before. in this new century hundreds of things still more astounding will be brought to light. at first people refuse to believe that a strange new thing can be done, then they begin to hope it can be done, then they see it can be done - then it is done and all the world wonders why it was not done centuries ago. one of the new things people began to find out in the last century was that thoughts - just mere thoughts - are as powerful as electric batteries - as good for one as sunlight is, or as bad for one as poison. to let a sad thought or a bad one get into your mind is as dangerous as letting a scarlet fever germ get into your body. if you let it stay there after it has got in you may never get over it as long as you live.
so long as Mistress Mary's mind was full of disagreeable thoughts about her dislikes and sour opinions of people and her determination not to be pleased by or interested in anything, she was a yellow-faced, sickly, bored and wretched child. circumstances, however, were very kind to her, though she was not at all aware of it. they began to push her about for her own good. when her mind gradually filled itself with robins, and moorland cottages crowded with children, with queer crabbed old gardeners and common little Yorkshire housemaids, with springtime and with secret gardens coming alive day by day, and also with a moor boy and his "creatures," there was no room left for the disagreeable thoughts which affected her liver and her digestion and made her yellow and tired.
so long as Colin shut himself up in his room and thought only of his fears and weakness and his detestation of people who looked at him and reflected hourly on humps and early death, he was a hysterical half-crazy little hypochondriac who knew nothing of the sunshine and the spring and also did not know that he could get well and could stand upon his feet if he tried to do it. when new beautiful thoughts began to push out the old hideous ones, life began to come back to him, his blood ran healthily through his veins and strength poured into him like a flood. his scientific experiment was quite practical and simple and there was nothing weird about it at all. much more surprising things can happen to any one who, when a disagreeable or discouraged thought comes into his mind, just has the sense to remember in time and push it out by putting in an agreeable determinedly courageous one. two things cannot be in one place.
where you tend a rose, a thistle cannot grow."