"The nineteenth century is perhaps most notable for an intellectual pluralism and a conflict of ideas to a degree never before witnessed. The philosophy of the Enlightenment, which emerged during the seventeenth century and reached its apogee in the eighteenth century, advocated the vigorous unrestricted application of argument and the studious appeal to evidence. It did not, in the nineteenth century, throw up one clear set of rationally based conclusions as to the nature of reality, knowledge, values and the best social order, as one might suppose it would given the ideals of argument and evidence."