Greek philosophers
Archelaus
Archelaus was a Greek philosopher who was born in Athens (or Miletus). He was a teacher of Socrates and a pupil of Anaxagoras.
His friend was the famous playwright Sophocles. The life of Archelas is mainly attested by Diogenes Laertios.
The works of Archelas have not survived, but they can be reconstructed from the works of Diogenes, Simplicius, Plutarch and Hippolytus of Rome. And so we know that he considered the air, which is produced by heating, to be a prelude. This is how the celestial bodies are formed. By heating and cooling the air, fire and water are created. All living things come from mud and have a soul within them.
Archelaus can be considered the forerunner of the sophists because he argued that people made their own laws and also established their own rulers. Thus, even who is just and who is not is not about the man himself, but about the agreement of men.
Archelaus was indeed a philosopher, but together with Socrates he participated in the Athenian expedition against the island of Samos in 441-439.