If the books which you read are your own, mark with a pen or pencil the most considerable things in them which you desire to remember. Then you may read that book the second time over with half the trouble, by your eye running over the paragraphs which your pencil has noted. It is but a very weak objection against this practice to say, I shall spoil my book; for I persuade myself that you did not buy it as a bookseller, to sell again for gain, but as a scholar, to improve your mind by it; and if the mind be improved, your advantage is abundant, through your book yields less money to your executors.

Isaac Watts (1674-1748) English theologian and hymnodist
Logic on the Right Use of Reason in the Enquiry after Truth (1724)
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