Slave-owners have indeed frequently shown great adroitness in defending this bad system; but, with few exceptions, they base their arguments upon the necessity of continuing slavery because it is already begun. Many of them have openly acknowledged that it was highly injurious to the prosperity of the State. The Hon. Henry Clay, in his address before the Colonization Society of Kentucky, has given a view of the causes affecting, and likely to affect, slavery in this country, which is very remarkable for its completeness, its distinctness, and its brevity. The following sentences are quoted from this address: "As a mere laborer, the slave feels that he toils for his master, and not for himself; that the laws do not recognise his capacity to acquire and hold property, which depends altogether upon the pleasure of his proprietor, and that all the fruits of his exertions are reaped by others. He knows that, whether sick or well, in times of scarcity or abundance, his master is bound to provide for him by the all-powerful influence of self-interest. He is generally, therefore, indifferent to the adverse or prosperous fortunes of his master, being contented if he can escape his displeasure or chastisement, by a careless and slovenly performance of his duties. "This is the state of the relation between master and slave, prescribed by the law of its nature, and founded in the reason of things. There are undoubtedly many exceptions, in which the slave dedicates himself to his master with a zealous and generous devotion, and the master to the slave with a parental and affectionate attachment. But it is my purpose to speak of the _general_ state of this unfortunate relation. "That labor is best, in which the laborer knows that he will derive the profits of his industry, that his employment depends upon his diligence, and his reward upon this assiduity. He then has every motive to excite him to exertion, and to animate him in perseverance. He knows that if he is treated badly, he can exchange his employer for one who will better estimate his service; and that whatever he earns is _his_, to be distributed by himself as he pleases, among his wife and children, and friends, or enjoyed by himself. In a word, he feels that he is a free agent, with rights, and privileges, and sensibilities. "Wherever the option exists to employ, at an equal hire, free or slave labor, the former will be decidedly preferred, for the reasons already assigned. It is more capable, more diligent, more faithful, and in every respect more worthy of confidence. "It is believed that nowhere in the _farming_ portion of the United States would slave labor be generally employed, if the proprietor were not tempted to raise slaves by the high price of the Southern market, which keeps it up in his own."