After supper I accompanied him to his apartment, and at my request he dictated to me an argument in favour of the negro who was then claiming his liberty, in an action in the Court of Session in Scotland. He had always been very zealous against slavery in every form, in which I with all deference thought that he discovered “a zeal without knowledge.” Upon one occasion, when in company with some very grave men at Oxford, his toast was, “Here's to the next insurrection of the negroes in the West Indies.” His violent prejudice against our West Indian and American settlers appeared whenever there was an opportunity. Towards the conclusion of his “Taxation no Tyranny,” he says, “how is it that we hear the loudest yelps for liberty among the drivers of negroes?” and in his conversation with Mr. Wilkes he asked, “Where did Beckford and Trecothick learn English?” That Trecothick could both speak and write good English is well known. I myself was favoured with his correspondence concerning the brave Corsicans. And that Beckford could speak it with a spirit of honest resolution even to his Majesty, as his “faithful Lord-Mayor of London,” is commemorated by the noble monument erected to him in Guildhall.
 The argument dictated by Dr. Johnson was as follows:
“It must be agreed that in most ages many countries have had part of their inhabitants in a state of slavery; yet it may be doubted whether slavery can ever be supposed the natural condition of man. It is impossible not to conceive that men in their original state were equal; and very difficult to imagine how one would be subjected to another but by violent compulsion. An individual may, indeed, forfeit his liberty by a crime; but he cannot by that crime forfeit the liberty of his children. What is true of a criminal seems true likewise of a captive. A man may accept life from a conquering enemy on condition of perpetual servitude; but it is very doubtful whether he can entail that servitude on his descendants; for no man can stipulate without commission for another. The condition which he himself accepts, his son or grandson perhaps would have rejected. If we should admit, what perhaps may with more reason be denied, that there are certain relations between man and man which may make slavery necessary and just, yet it can never be proved that he who is now suing for his freedom ever stood in any of those relations. He is certainly subject by no law, but that of violence, to his present master; who pretends no claim to his obedience, but that he bought him from a merchant of slaves, whose right to sell him never was examined. It is said that according to the constitutions of Jamaica he was legally enslaved; these constitutions are merely positive; and apparently injurious to the rights of mankind, because whoever is exposed to sale is condemned to slavery without appeal; by whatever fraud or violence he might have been originally brought into the merchant's power. In our own time Princes have been sold, by wretches to whose care they were entrusted, that they might have an European education; but when once they were brought to a market in the plantations, little would avail either their dignity or their wrongs. The laws of Jamaica afford a negro no redress. His colour is considered as a sufficient testimony against him. It is to be lamented that moral right should ever give way to political convenience. But if temptations of interest are sometimes too strong for human virtue, let us at least retain a virtue where there is no temptation to quit it. In the present case there is apparent right on one side, and no convenience on the other. Inhabitants of this island can neither gain riches nor power by taking away the liberty of any part of the human species. The sum of the argument is this: No man is by nature the property of another: The defendant is, therefore, by nature free: The rights of nature must be some way forfeited before they can be justly taken away: That the defendant has by any act forfeited the rights of nature we require to be proved; and if no proof of such forfeiture can be given, we doubt not but the justice of the court will declare him free.”
 I record Dr. Johnson's argument fairly upon this particular case; where, perhaps, he was in the right. But I beg leave to enter my most solemn protest against his general doctrine with respect to the Slave Trade. For I will resolutely say that his unfavourable notion of it was owing to prejudice, and imperfect or false information. The wild and dangerous attempt which has for some time been persisted in to obtain an act of our Legislature, to abolish so very important and necessary a branch of commercial interest, must have been crushed at once, had not the insignificance of the zealots who vainly took the lead in it, made the vast body of Planters, Merchants, and others, whose immense properties are involved in that trade, reasonably enough suppose that there could be no danger. The encouragement which the attempt has received excites my wonder and indignation; and though some men of superiour abilities have supported it; whether from a love of temporary popularity, when prosperous; or a love of general mischief when desperate, my opinion is unshaken. To abolish a status, which in all ages God has sanctioned, and man has continued, would not only be robbery to an innumerable class of our fellow-subjects; but it would be extreme cruelty to the African Savages, a portion of whom it saves from massacre, or intolerable bondage in their own country, and introduces into a much happier state of life; especially now when their passage to the West Indies and their treatment there is humanely regulated. To abolish that trade would be to
“ shut the gates of mercy on mankind.”
 Whatever may have passed elsewhere concerning it, the HOUSE OF LORDS is wise and independent:
Intaminatis fulget honoribus;
Nec sumit aut ponit secures
Arbitrio popularis auræ.
 I have read, conversed, and thought much upon the subject, and would recommend to all who are capable of conviction, an excellent Tract by my learned and ingenious friend John Ranby, Esq. entitled “Doubts on the Abolition of the Slave Trade.” To Mr. Ranby's “Doubts,” I will apply Lord Chancellor Hardwicke's expression in praise of a Scotch Law Book, called “Dirleton's Doubts”; “HIS Doubts, (said his Lordship,) are better than most people's Certainties.”
 When I said now to Johnson, that I was afraid I kept him too late up, “No, Sir, (said he,) I don't care though I sit all night with you.” This was an animated speech from a man in his sixty-ninth year.
 Had I been as attentive not to displease him as I ought to have been, I know not but this vigil might have been fulfilled; but I unluckily entered upon the controversy concerning the right of Great-Britain to tax America, and attempted to argue in favour of our fellow-subjects on the other side of the Atlantick. I insisted that America might be very well governed, and made to yield sufficient revenue by the means of influence, as exemplified in Ireland, while the people might be pleased with the imagination of their participating of the British constitution, by having a body of representatives, without whose consent money could not be exacted from them. Johnson could not bear my thus opposing his avowed opinion, which he had exerted himself with an extreme degree of heat to enforce; and the violent agitation into which he was thrown, while answering, or rather reprimanding me, alarmed me so, that I heartily repented of my having unthinkingly introduced the subject. I myself, however, grew warm, and the change was great, from the calm state of philosophical discussion in which we had a little before been pleasingly employed.
 I talked of the corruption of the British Parliament, in which I alledged that any question, however unreasonable or unjust, might be carried by a venal majority; and I spoke with high admiration of the Roman Senate, as if composed of men sincerely desirous to resolve what they should think best for their country. My friend would allow no such character to the Roman Senate; and he maintained that the British Parliament was not corrupt, and that there was no occasion to corrupt its members; asserting, that there was hardly ever any question of great importance before Parliament, any question in which a man might not very well vote either upon one side or the other. He said there had been none in his time except that respecting America.
 We were fatigued by the contest, which was produced by my want of caution; and he was not then in the humour to slide into easy and cheerful talk. It therefore so happened, that we were after an hour or two very willing to separate and go to bed.
 About this time I wrote to Johnson, giving him an account of the decision of the Negro cause, by the Court of Session, which by those who hold even the mildest and best regulated slavery in abomination, (of which number I do not hesitate to declare that I am none,) should be remembered with high respect, and to the credit of Scotland; for it went upon a much broader ground than the case of Somerset, which was decided in England; being truly the general question, whether a perpetual obligation of service to one master in any mode should be sanctified by the law of a free country. A negro, then called Joseph Knight, a native of Africa, having been brought to Jamaica in the usual course of the slave trade, and purchased by a Scotch gentleman in that island, had attended his master to Scotland, where it was officiously suggested to him that he would be found entitled to his liberty without any limitation. He accordingly brought his action, in the course of which the advocates on both sides did themselves great honour. Mr. Maclaurin has had the praise of Johnson, for his argument in favour of the negro, and Mr. Macconochie distinguished himself on the same side, by his ingenuity and extraordinary research. Mr. Cullen, on the part of the master, discovered good information and sound reasoning; in which he was well supported by Mr. James Ferguson, remarkable for a manly understanding, and a knowledge both of books and of the world. But I cannot too highly praise the speech which Mr. Henry Dundas generously contributed to the cause of the sooty stranger. Mr. Dundas's Scottish accent, which has been so often in vain obtruded as an objection to his powerful abilities in parliament, was no disadvantage to him in his own country. And I do declare, that upon this memorable question he impressed me, and I believe all his audience, with such feelings as were produced by some of the most eminent orations of antiquity. This testimony I liberally give to the excellence of an old friend, with whom it has been my lot to differ very widely upon many political topicks; yet I persuade myself without malice. A great majority of the Lords of Session decided for the negro. But four of their number, the Lord President, Lord Elliock, Lord Monboddo, and Lord Covington, resolutely maintained the lawfulness of a status, which has been acknowledged in all ages and countries, and that when freedom flourished, as in old Greece and Rome.