The Advancement of Philosophy is Dependent on Liberty
To advance culture philosophically (not just technologically or economically) liberty is required. The major philosophical works came from liberal nations.
TIP: Another way to phrase this is “the liberty of the press (and other first Amendment rights) have a direct relation to the advancement of philosophy (as one must be able to think and speak freely to advance the art of thinking).”
TIP: When we say “liberal nations” we mean Liberal as in an ideology that supports “popular governments,” free speech, freedom of the press, etc. We don’t mean “modern American Socially Progressive Liberalism” specifically.
The Idea that Liberty and Philosophy are Mutually Dependent
Most enlightened written works arise out of just states, and most despotic states produce a lack of enlightened works.
This was true for Plato and Aristotle who lived in Athens, for Livy of Rome, for Machiavelli of Florence, and for all the Enlightenment philosophers.
It was true for Hume, who discussed the idea in his essays in Essays, Moral, Political, and Literary (Part I.II of Liberty and the Press), and for many others.
This isn’t to say that tyranny doesn’t produce philosophy if you see George III as a tyrant and Madison as a philosopher, or Locke as a philosopher and James II as a Tyrant, then certainly it can, but that isn’t a fully correct view.
The English Kings may have been tyrannical in some respects, but the world has certainly known worse states. In truth, few nations up to that point had been as free as George III’s America or James II’s England (that less a kindness to George or James, and more a comment on the rest of history).
Liberty and equality, but almost foremost liberty, is the secret sauce of everything good about our existence as humans.
Liberty and equality are the two values that create the core of liberalism and democracy, they are implied by republicanism, and they have long been considered virtues (when they are in the balance at least).
With that in mind, it is not liberty unrestrained that is a virtue, but true liberty (which is naturally meant to be restrained, as unrestrained liberty is anarchy).
The concept is simple, to advance philosophy one must be able to write freely. Likewise, free speech, free press, and freedom of association are paramount as well.
Only in times when philosophers are free to speak without a fear of tyrannical oppression can the best philosophy be written, only when people are comfortable enough to sit around and think can the best philosophy be written.
The exception to this is that philosophers are driven to write in times when liberty was at risk of being taken away, such as the case for Cicero, Machiavelli, Locke or Madison.
Broadly: Life, Liberty, AND the Pursuit of Happiness are all Required
With that in mind, we can state this more broadly as life, liberty, and the pursuit of happiness are all required to produce great works of philosophy. Here we find the importance of equality.
The Importance of Equality
If basic needs are not met, we could very well find our philosopher kings begging for alms on the street while oligarchs rain and horde resources. In an environment like this, great works may be created, but one would be assured to see less. This is why concepts like “Second Rights” are important.
The Problems of Excess
Philosophy requires liberty, but excesses of liberty and equality are corrupting. How do we know this? We in the west have ensured times of liberty and equality from which philosophy could arise that guided us toward more democratic times.
With that said, once liberty has been gained, then the balancing act of the many virtues is required, and we get the technocratic impossibilities of sustaining a government that reflects the highest values (and respects the lowest).
This has many pitfalls, and things can get tricky.
Still, while this thought process could fill books, the only point here is: Philosophy requires liberty. Thus anyone who loves wisdom must love liberty, and anyone who loves liberty must seek to temper it before it creates a tyrant. Life is complex.