From pg 330 of Charlotte Mason's Home Education:
'I am, I ought, I can, I will'--these are the steps of that ladder of St. Augustine, whereby we
"rise on stepping stones
Of our dead selves to higher things."
'I am'--we have the power of knowing ourselves. 'I ought'--we have within us a moral judge, to whom we feel ourselves subject, and who points out and requires of us our duty. 'I can'--we are conscious of power to do that which we perceive we ought to do. 'I will'--we determine to exercise that power with a volition which is in itself a step in the execution of that which we will. Here is a beautiful and perfect chain, and the wonder is that, so exquisitely constituted as he is for right-doing, error should be even possible to man. But of the sorrowful mysteries of sin and temptation it is not my place to speak here; you will see that it is because of the possibilities of ruin and loss which lie about every human life that I am pressing upon parents the duty of saving their children by the means put into their hands. Perhaps it is not too much to say, that ninety-nine out of a hundred lost lives lie at the door of parents who took no pains to deliver them from sloth, from sensual appetites, from willfulness, no pains to fortify them with the habits of a good life.
What her contemporaries wrote:
"I am, I can, I ought, I will. This was the motto she gave us. I am a human being, one of God's children; I can do right by my fellowmen and by myself; I ought so to do and God help me, I will so do. Is this not a great message she has given us?"
(Michael A. E. Franklin, one of Charlotte Mason's students; from In Memoriam)
"I am, I can, I ought, I will. Miss Mason chose your inspiring motto. You can say,
I am the greatest thing in God's creation: a human being with a spark of God's divine spirit in my body. Because I belong to the human family I can do the great things that other human beings have done. I have powers of doing, thinking and loving.
I can use these powers. I can change my thoughts from things that harm me and that worry me to the beautiful things I have learnt in my School: I can know the ways of activity, I can think kindly thoughts of God's creatures in the past and in the present, in this and other countries, of people who do not think as I do in religion and politics.
I ought to do these things: I owe it to my God, my parents and my School.
I will forget myself, and live up to the ideals of my School.
God is on the side of those who will, and with His help we will all go on working as Miss Mason hoped we would."
(By the Hon. Mrs. Franklin, from In Memoriam)
This is how it was rendered for the online modern English paraphrase of Volume 1:
"I am, I ought, I can, I will. These are like four steps of the ladder that St. Augustine wrote about when he said we could 'go up on the stepping stones of the old, sinful man we cast off and are dead to, and ascend to higher things.' I am means that we can know ourselves and understand what we're really like. I ought means that we have a moral judge inside us. We feel like we're subject to it. It lets us know what our duty is and compels us to do it. I can means that we know we have the ability to do what we know we're supposed to. I will means that we resolve to use the ability we know we have to do what our inner moral judge has urged us to do. Resolve is the first step in actually doing. These four make a perfect, beautiful chain . . ."