Either I am very much mistaken, or Locke the definer has very well defined liberty as "power." I am mistaken again, or Collins, celebrated London magistrate, is the only philosopher who has really sifted this idea, and Clark's answer to him was merely that of a theologian. But of all that has been written in France on liberty, the following little dialogue seems to me the most clear.
A: There is a battery of guns firing in your ears, have you the liberty to hear them or not to hear them?
B: Without doubt, I cannot stop myself hearing them.
A: Do you want this gun to carry off your head and the heads of your wife and daughter, who are walking with you?
B: What are you talking about? as long as I am of sound mind, I cannot want such a thing; it is impossible.
A: Good; you hear this gun necessarily, and you wish necessarily that neither you nor your family shall die from a cannon shot while you are out for a walk; you have not the power either of not hearing or of wishing to remain here?
A: You have consequently taken some thirty steps in order to be sheltered from the gun, you have had the power to walk these few steps with me?
B: Again very clearly.
A: And if you had been a paralytic, you could not have avoided being exposed to this battery, you would necessarily have heard and received a gun shot; and you would be dead necessarily?
B: Nothing is more true.
A: In what then does your liberty consist, unless it be in the power that your self has exercised in performing what your will required of absolute necessity?
B: You embarrass me; liberty then is nothing but the power of doing what I want to do?
A: Think about it, and see if liberty can be understood otherwise.
B: In that case my hunting dog is as free as I am; he has necessarily the will to run when he sees a hare, and the power of running if he has not a pain in his legs. I have then nothing above my dog; you reduce me to the state of the beasts.
A: What poor sophistry from the poor sophists who have taught you. Indeed you are in a bad way to be free like your dog! Do you not eat, sleep, propagate like him, even almost to the attitude? Do you want the sense of smell other than through your nose? Why do you want to have liberty otherwise than your dog has?
B: But I have a soul which reasons much, and my dog reasons hardly at all. He has almost only simple ideas, and I have a thousand metaphysical ideas.
A: Well, you are a thousand times freer than he is; that is, you have a thousand times more power of thinking than he has; but you do not think otherwise than he does.
B: What! I am not free to wish what I wish?
A: What do you mean by that?
B: I mean what everyone means. Doesn't one say every day, wishes are free?
A: A proverb is not a reason; explain yourself more clearly.
B: I mean that I am free to wish as I please.
A: With your permission, that has no sense; do you not see that it is ridiculous to say, I wish to wish? You wish necessarily, as a result of the ideas that have offered themselves to you. Do you wish to be married; yes or no?
B: But if I tell you that I want neither the one nor the other?
A: You will be answering like someone who says: "Some believe Cardinal Mazarin to be dead, others believe him to be alive, and as for me I believe neither the one nor the other."
B: Well, I want to be married.
A: Ah! that is an answer. Why do you want to be married?
B: Because I am in love with a beautiful, sweet, well-bred young girl, who is fairly rich and sings very well, whose parents are very honest people, and because I flatter myself I am loved by her, and very welcome to her family.
A: That is a reason. You see that you cannot wish without reason. I declare to you that you are free to marry; that is, that you have the power to sign the contract, have your nuptials, and sleep with your wife.
B: How now! I cannot wish without reason? And what will become of that other proverb: Sit pro ratione voluntas; my will is my reason, I wish because I wish?
A: That is absurd, my dear fellow; there would be in you an effect without a cause.
B: What! When I play at odds and evens, I have a reason for choosing evens rather than odds?
A: Yes, undoubtedly.
B: And what is that reason, if you please?
A: The reason is that the idea of even rather than the opposite idea presents itself to your mind. It would be comic that there were cases where you wished because there was a cause of wishing, and that there were cases where you wished without any cause. When you wish to be married, you evidently feel the dominating reason; you do not feel it when you are playing at odds and evens; and yet there certainly must be one.
B: But, I repeat, I am not free then?
A: Your will is not free, but your actions are. You are free to act, when you have the power to act.
B: But all the books I have read on the liberty of indifference....
A: What do you mean by the liberty of indifference?
B: I mean the liberty of spitting on the right or on the left, of sleeping on my right side or on my left, of taking a walk of four turns or five.
A: Really the liberty you would have there would be a comic liberty! God would have given you a fine gift! It would really be something to boast of! Of what use to you would be a power which was exercised only on such futile occasions? But the fact is that it is ridiculous to suppose the will to wish to spit on the right. Not only is this will to wish absurd, but it is certain that several trifling circumstances determine you in these acts that you call indifferent. You are no more free in these acts than in the others. But, I repeat, you are free at all times, in all places, as soon as you do what you wish to do.
B: I suspect you are right. I will think about it.
 See "Free-Will."
Sorry, no summary available yet.