Saint-Simon’s work forms a kind of synthesis of several strands in the French philosophy around the time of Revolution. Firstly, we might note his enthusiasm for scientific progress. In a manner reminiscent of Condorcet, Saint-Simon describes in his writings the supposed development of humanity from the most primitive stages to the current European society. Remarkably, Saint-Simon, just like Lamarck, supposes that there’s no great difference between animals and humans. Humans just happen to have the best organised societies and by means of this organisation and skills of reasoning based on language they have been able to take control of Earth. If humans would for some reason disappear, another animal species would most likely take over and go through same phases of development - Saint-Simon places his bet on beavers.
The development of humanity, as envisioned by Saint-Simon, follows especially the development of religion. Here, an innovation is first made by a select group in one culture, but it becomes popular only in the next stage of development. Thus, Egyptian priests had already replaced crude magic with complex polytheism, but it was only Greeks who really made polytheism into a popular religion, while monotheism of Socrates was later followed by Christianity. The next stage in this progress of metaphysical systematisation had been gradual replacement of God with the notion of the laws of nature, which would some day, Saint-Simon predicted, be reduced into a single overarching law.
Saint-Simon, just like Maine de Biran, wanted to situate himself philosophically between the schools of speculative rationalism and empiricsism, or as Saint-Simon called them, a priori Platonism and a posteriori Aristotelianism. Like most French philosophers of the time, Saint-Simon favoured the empirical side of the dispute, but noted that a true scientific discourse would need both methods. The a priori side was especially important for Saint-Simon, because it was an important route to the study of human life.
This study of human behaviour, and especially the behaviour of human societies, was were Saint-Simon thought the next scientific breakthrough should appear. Here Saint-Simon’s theoretical interests meet another strand of his thought, namely, his desire for practical changes in the society. Saint-Simon notes that mere theoretical collection of information serves no purpose in human life, but it must happen in interaction with a more practically oriented development of society, which on its part would be completely blind without the guidance of good theories. The first fruit of such an interaction was L'Industrie, a series of pamphlets containing articles from notable scholars on such themes as economy and politics. Although Saint-Simon did not write all of this text, his ideas set the tone for the whole work.
Although Saint-Simon so envisages a sort of symbiosis between theory and practice, he clearly seems to favour the practical side of the equation - the worth of theory lies in its use in practice, not e.g. in pure enjoyment of theory as such. Indeed, he is highly critical of any idlers, who serve no purpose in a society. Although Saint-Simon’s main target are obviously nobles and clergy and he does appreciate e.g. the life of a scientist or philosopher, this evaluation of an individual being on basis of the work he does seems quite peculiar in a time, when technological advancement might make the work of some people completely unnecessary.
Saint-Simon’s dislike of nobles is no secret. Indeed, he takes nobility to be a remnant of feudal times, in which military might was the important factor in social relations. While the economy of ancient Greek and Rome had been based on slavery, the economy of Europe in Middle Ages was based on the control of land and serfs tilling it, while this control was ultimately founded on a historical conquest of Rome by barbarian soldiers. The other side of feudalism was in Saint-Simon’s eyes legalism, which was just another form of control - lawyers merely defined who was to rule whom. Thus, French Revolution, overtaken by legalists like Robespierre, soon plunged into a dictatorship and finally reverted back to feudalism in the emperorship of Napoleon.
A true social change away from feudalism to what Saint-Simon called industrialist society would actually be peaceful, he stated, because its instigators - the class of industrialists or those who did the actual work - were by nature peaceful and understood that war and anarchy is bad for business. Thus, Saint-Simon spoke for a relatively peaceful move away from absolute into a constitutional monarchy, where the state still had a feudalist remnant in the shape of king, while the parliament was a sign of a more modern society. Then again, he thought this form of state would be only a temporary way station toward a truly industrialist society.
If Saint-Simon’s idea of a peaceful reformation of society seems quite idealistic in light of the future events of history, even more naive seems his opinion that the rise of industrialism and abolition of feudalism would obliterate all warfare. Saint-Simon speaks of a union of European states into one constitutional monarchy and quite optimistically hopes that industrialists of England and France would sway their governments into uniting their countries and that the rest of Europe would eventually have to bow to the superiority of these two nations. Saint-Simon did not foresee the rise of nationalism, which would plunge Europe into even more terrible wars and which still hinders a total unification of Europe, even if it seems closer than in Saint-Simon’s days.