Even so, why not Aristotle and Plato, whom we are discussing today?

It is precisely because they did not provide later philosophers and the subsequent development of philosophy with those truly original philosophical questions that are unique to them and have a profound impact on later philosophy.

That is to say, they have not truly entered the realm of thought, or the realm of philosophical concepts. This realm of thought or philosophical concepts is usually referred to as the realm of metaphysics.

So, having understood this issue, we can more clearly know why Montesquieu, when he defined law as the necessary relationship produced by the natural nature of things, was in a contradictory mental state.

Here, I would like to quote a philosopher, Isaiah Berlin, on his evaluation of the French Enlightenment. In his famous book, "The Age of Enlightenment", he discussed the French Enlightenment thinkers, especially those represented by Montesquieu, Voltaire, and Diderot, and the intrinsic connection between their ideas and those of their teachers, namely, British philosophers such as Locke and Hume.

He particularly pointed out that if British philosophers were an attempt to shape philosophy based on science, French thinkers, on the other hand, sought to continue the unfinished work of their predecessors. However, they did not complete this task well, and in the process of doing so, they themselves created new difficulties and problems.

For in the empiricist philosophy of Britain, hardly any philosopher doubted that the account of the empirical world they constructed had a significance that transcended the era in which they lived.

For instance, whenever we read Bacon's works, Berkeley's works, or those of Locke and Hume, we will find that they have a "capital I" to represent humanity. While their ideas were still in their minds, the concept of "I" they understood was not the speaker at the moment, let alone the philosopher himself, but rather represented the "universal cognition" of humanity.

For this point, we particularly need to read Locke's work, "An Essay Concerning Human Understanding", and we can then more profoundly feel that the reason why they put the philosopher's own understanding of this matter in the name of humanity and present it in the form of common human experience is that they believe their understanding of things and their understanding of human nature have far exceeded that of any specific individual and have risen to the level of universal knowledge that we can constitute.

I think in this regard, British philosophers do not see a contradiction between any individual's past experiences and activities and universal human knowledge. And it is precisely because scientific knowledge itself has provided us with a good model, which is that as long as we conduct experiments and rely on strict data, that is, through logical reasoning, we can form a precise set of knowledge. Both of these parts have a universality that transcends individual existence.

If it lacks universality, how can science exist? How can it progress?

It must have a universal significance that such universal significance can be applied to all aspects of human knowledge. So, in this sense, for the British empiricists, they do not encounter the problems that French philosophers face.

However, it is precisely the French philosophers who have not fully realized what they have learned from the British philosophers, such as how scientific methods can be applied or better applied in human social life. This should be said to be an important issue faced by French thinkers.

Just as we mentioned earlier, the science of the 17th century adopted the British empiricism of the 17th century, and the British empiricism of the 17th century provided us with universal knowledge about the world. This knowledge or its significant outcome lies in that it broke the previous philosophers' vague, mysterious and indescribable understanding of the world.

At that time, human understanding of the world was entirely based on a certain philosopher. His perception of the world, and then he described this perception to us, telling us that the world is exactly as "I" perceive it. If you want to know what the world is like, then go and perceive it yourself.

However, such an approach does not bring us science. The concept of science must be external to the perception of each of us as individuals, external to our individual experiences, and constitute a set of empirical knowledge that is verifiable, experimentable, observable, and even repeatable.

At this point, British philosophers, having completed their work, had ceded to experimental science the mechanics, physics, and all the natural sciences that had previously been within the purview of philosophy. Philosophy was thus compelled to acknowledge that it had no place in these natural domains and should not play a role in them at all. So, what did the philosophers focus on instead?

It is people, as well as the inner activities of people, that are more concerned with people's hearts and souls. Of course, if we take it one step further, we will pay attention to people's morality.

However, science has provided us with successful experiences. That is to say, when science can describe our external world in a strict and economic way, it offers us a reliable or a knowledge that we all can recognize. At this point, philosophers suddenly find that we need to extend the achievements of science to other research fields of philosophy, so that other research fields of philosophy can also benefit from the achievements of science. If science can be utilized in all fields of human knowledge, wouldn't it be a good thing for philosophy?

That is to say, philosophy can also be constructed in a scientific way. Therefore, when 17th-century British philosophy took science as its model, this statement itself is merely an interpretation given by us today when we look back at that period of history.

But in fact, how is it?

In fact, philosophers have tried subjectively to push all the achievements made by science into all areas of philosophy, including human social life, economic life, and even the more unpredictable psychological world of human beings.

If we say that no matter how philosophy changes and no matter how much of its territory is swallowed up or occupied by science, there is always one area that science cannot encroach upon. This area is the realm of the inner world of human beings.

Therefore, we often say that the human mind is the most difficult to describe, to express and to explain. That's why later on Hegel came up with his "Phenomenology of Spirit", which tells us that our concept of mind cannot be described by scientific methods. If we were to describe the mind using scientific methods, we would only be able to arrive at what is known as "psychology" in experimental sciences.

So, in this sense, a philosopher always has to hold onto his own territory, which is the territory concerning the human mind. But how is the human mind to be known?

Of course, the human mind is recognized through human behavior. If we do not have human behavior, you cannot talk about the human mind because you cannot observe the mind directly. You must perceive and understand it through behavior.

This leads to a conclusion, therefore, what human behavior is, it is not an individual thing, it must be a social behavior. So, the discussion of the concept of the mind has entered a social level.

Society is composed of individual people. Therefore, at this point, how to understand the intrinsic relationships among individuals within society becomes an important issue for philosophy to discuss.

This is why, among the British empiricist philosophers, almost all of them would engage in discussions about social issues and eventually about political matters. Why would a philosopher like Locke write a book like "Two Treatises of Government", and why would people like Hume in Britain have their own political philosophy theories?

Hume's political philosophy is based on his ethics, that is, the so-called sentimental ethics. It is precisely on this dimension that French philosophers discovered a vast space for their endeavors. It is precisely on this dimension that they found that if they were to solve the problem of the mind, the first thing they needed to address was society.

This is also the reason why the Enlightenment in France was more than just an intellectual awakening; it was more about religious enlightenment and social enlightenment. This is the underlying cause behind it.

So, with this background in place, the work done by French thinkers was not entirely driven by the personal interests or limited knowledge of any single thinker. Instead, it fully reflected the common concerns of philosophers of that era. This is why the philosophers of the 18th-century Enlightenment are regarded as a whole, seen as having a unified program, a unified path, unified principles, and even forming some unified ideological concepts, constituting a grand ideological movement.

It was not a solitary fight. Almost all the thinkers of the Enlightenment were upholding a common belief, which was to transform society.