20. The Enlightenment
Before I move on to the big subject of knowledge and truth, let me first, as an intermezzo, give a thumbnail sketch of the Enlightenment and Romanticism as two major movements of thought in western civilization.
Western culture has to a large extent been rooted in the Enlightenment. There lies an important source of the view of the self as rational, autonomous and capable of making its own future.
The Enlightenment is variegated. Jonathan Israël distinguished between a radical stream and a moderate, mainstream one. In the radical stream we find Spinoza, Bayle, and the French radical philosophes (such as Diderot, d’Alembert, d’Holbach, Helvétius, and Condorcet). In the moderate stream we find many of the British enlightenment thinkers (such as Locke, Adam Smith, and Newton) and in France Turgot, Montesquieu and Voltaire. Some philosophers (David Hume, Jean-Jacques Rousseau) are difficult to assign clearly to one of the streams.
There are four central issues on which the two streams differ. A first is whether there is (in case of the radicals) or is not (the moderates) a unity of mind and body. According to the radicals thinking arises from the body, without agency from any external God, and hence there is no immortality of the soul and no hereafter. According to the moderates thinking is infused by God. Separation of mind and body is required for immortality of the soul, which is needed for morality.
The second central issue concerns rationality. Are human beings capable (the radicals) or not (the moderates) of rational autonomy of the self and rational arrangements for a good society. According to the moderates, rationality has its limits and human thought and action depend on habits and on social and institutional conditions.
A third issue is the classic problem of universals, which I discussed in a previous item in this blog. For the radical stream conduct must be guided by universal principles of reason, with a universal notion of the individual, while the mainstream had an eye for the limits of reason, the role of unique individuals, institutions, customs, norms, unintended consequences of social dynamics (Hume), diversity of societies on the basis of climate, location, environment and religion (Montesquieu), and technology and entrepreneurship (Turgot). It is often not so much a mistake, an error of reason, that is in the way of truth and goodness as existing habits, routines, laxity, established interests and resistance to change. The radical stream is a-historical, the moderate stream is not.
Fourthly, there is a difference of opinion whether there is free will (the moderates) or not (most radicals). I discussed free will in a previous item of this blog.
On the four points of difference one can take a moderate position on one and a radical position on another. One can maintain that there is no separation of body and mind, that thinking arises in the body, there is no providential, miracle-producing God (radical), and no immortality of the soul (radical). One can doubt the rationality of the human being and society (moderate) and one can doubt the validity or immutability of universal ideas and rules (moderate). That is more or less where I stand.