cannot infringe on another's natural rights, as every man is equal and has the same inalienable rights. These natural rights include perfect equality and freedom, as well as the right to preserve life and property. Locke argues against indentured servitude on the basis that enslaving oneself goes against the law of nature because a person cannot surrender their own rights: freedom is absolute, and no one can take it away. Locke argues that one person cannot enslave another because it is morally reprehensible, although he introduces a caveat by saying that enslavement of a lawful captive in time of war would not go against one's natural rights. As a spill-over of the Enlightenment, nonsecular beliefs expressed first by Quakers and then by Protestant evangelicals in Britain and the United States emerged. To these groups, slavery became "repugnant to our religion" and a "crime in the sight of God". These ideas added to those expressed by Enlightenment thinkers, leading many in Britain to believe that slavery was "not only morally wrong and economically inefficient, but also politically unwise." This ideals eventually led to the abolition of slavery in Britain and the United States. Enlightened absolutism The leaders of the Enlightenment were not especially democratic, as they more often look to absolute monarchs as the key to imposing reforms designed by the intellectuals. Voltaire despised democracy and said the absolute monarch must be enlightened and must act as dictated by reason and justice—in other words, be a "philosopher-king". In several nations, rulers welcomed leaders of the Enlightenment at court and asked them to help design laws and programs to reform the system, typically to build stronger states. These rulers are called "enlightened despots" by historians. They included Frederick the Great of Prussia, Catherine the Great of Russia, Leopold II of Tuscany and Joseph II of Austria. Joseph was over-enthusiastic, announcing many reforms that had little support so that revolts broke out and his regime became a comedy of errors, and nearly all his programs were reversed. Senior ministers Pombal in Portugal and Johann Friedrich Struensee in Denmark also governed according to Enlightenment ideals. In Poland, the model constitution of 1791 expressed Enlightenment ideals, but was in effect for only one year before the nation was partitioned among its neighbors. More enduring were the cultural achievements, which created a nationalist spirit in Poland. Frederick the Great, the king of Prussia from 1740 to