Shouldn’t you then even be able to love those who hate you, only because you are good? That is what St. Augustine suggested. And, even more demanding, shouldn’t we be grateful to those who torment and torture us because, as suggested by St. Thomas, that is what creates a God-like patience in us?

If Plato is a realist or an idealist can very much be discussed. That he was wise to turn all questions up and down and to look upon them from every point of view, so much is clear. Here, however, you find his demand for “philosopher kings” which, given human history, seems utterly idealistic. But is it really so, in a world of atomic weapons?

At the other end of the Park you have the famous poet and drunkard Francois Villon who, half a millennium ago, bitterly lamented that he hadn’t studied enough in his foolish youth. Do your children do so?

Take a few steps more and sit down on the bench close to one who truly studied all through is life, Voltaire and ask yourself if his irony against Leibniz was correct. Do we, or don’t we live in the best of all possible worlds ? If you, like Voltaire, say that we don’t, do tell us how we, realistically, can make it better! Or are you, as well as the great man, only advancing empty idealism?

Another one extremely erudite, Immanuel Kant, has a most ironic idea of the crooked timber of mankind, which seems realistic. But then he became famous for the recipe, that you should always act so that your actions could be made into general laws. Knowing yourself, isn’t that a bit idealistic?

Why do I place the great French father of sociology, Émile Durkheim, close to the King’s bench, among idealists? He came close to what I consider one step forward in our thinking, that of biological “co-thinking Superbrains” now ruling the world. But he missed it because he came close to Condorcet in thinking that no biological explanation was ever permitted if a sociological one was possible.

Not far from Durkheim you also find Ludwig Wittgenstein who was idealistic enough to believe it was useful to tell the ignorant experts as well as the masses that “whereof one cannot speak, thereof one must be silent”. He hadn’t experienced modern media.

During the last three million years Nature has created about one million billion, 10¹⁵ or 1.000.000.000.000.000, connections between different small units inside our human brains. This is what makes it possible for us to dream any crazy dreams, asleep or awake. One way to find a difference between them is to realize that idealists are more easily seduced by beautiful dreams than realists.

One such idealist was, as I said in the beginning, Condorcet, whom I have hidden in a one-way alley. A few years into the French Revolution he finished a now famous book with the promise to mankind that all types of limiting chains had now, thanks to the revolution, fallen away from mankind. Instead we were now given total freedom to create any kind of perfect society that we might wish.

Only a very short time after he had written this, his liberty hubris was punished. He was himself put into chains in one of the prisons of the Revolution, where he was left to die.

A few steps up you will find Albert Einstein, who was mentioned above, and to the left of him Jean Jacques Rousseau, who like Condorcet had a clearly exaggerated opinion about the level of freedom, but this time the liberty of primitive savages.

A short way after him you can read Descartes famous “cogito, ergo sum”, “I think, thus I exist”. I am not convinced. Wouldn’t you, too, agree that “famesco, ergo sum”, “I am hungry, thus I exist” is a much more truthful expression? Because, surely, hunger came much before thinking!

In another one-way alley behind Descartes  Pico della Mirandola is hidden. He suggests that the one million billion brain-connections, man’s intelligence, might possibly tame our hottest emotions. Isn’t that one of mankind’s most important questions, if we now want to avoid a fourth world war? But so far it has been little but an idealistic dream.

One who didn’t think kings or laws could do much to help us was Samuel Jonson. The responsibility rests with ourselve. One who, on the contrary, thought that the state could bring perfect happiness to all was Karl Marx. His communist ideas carried Russia down in an abyss, similar to the one you can find right behind his inscription. Surely, also Marx was a great idealist!

Neither should you believe much in the ideas of Marx’ closest neighbour, Walter Gilbert, or others geneticists who imagine they can cure mankind’s deceases by genetic engineering of our germline, that is, of our genetic inheritance. Or might society be cured because it is like a machine which you can make ever better? Cournot, an old type engineer, played with that idea. It has been shared by many of those who want to believe in “historical progress”.

Was Darwin really an idealist? Sure! He was a very good analytical realist, but his heart did not like what his head found! Can’t we see him as a perfect example of “a head full of realism and a heart full of idealism”! Don’t you, too, have a bit of such a mixture?

Could such a mixture even be true for Hobbes? He had a most ugly description of a reality that most of Europe has escaped for a few hundred years. But don't these horrors sometimes threaten to come back?