[Side-note: These early theorists are not known from their own writings, which have been lost. Importance of the information of Aristotle about them.]
It is a misfortune that we do not possess a complete work, or even considerable fragments, from any one of these philosophers, so as to know what their views were when stated by themselves, and upon what reasons they insisted. All that we know is derived from a few detached notices, in very many cases preserved by Aristotle; who, not content (like Plato) with simply following out his own vein of ideas, exhibits in his own writings much of that polymathy which he transmitted to the Peripatetics generally, and adverts often to the works of predecessors. Being a critic as well as a witness, he sometimes blends together inconveniently the two functions, and is accused (probably with reason to a certain extent) of making unfair reports; but if it were not for him, we should really know nothing of the Hellenic philosophers before Plato. It is curious to read the manner in which Aristotle speaks of these philosophical predecessors as "the ancients" ([Greek: oi( a)rchai=oi]), and takes credit to his own philosophy for having attained a higher and more commanding point of view.[1]
[Footnote 1: Bacon ascribes the extinction of these early Greek philosophers to Aristotle, who thought that he could not assure his own philosophical empire, except by putting to death all his brothers, like the Turkish Sultan. This remark occurs more than once in Bacon (Nov. Org. Aph. 67; Redargutio Philosoph. vol. xi. p. 450, ed. Montagu). In so far as it is a reproach, I think it is not deserved. Aristotle's works, indeed, have been preserved, and those of his predecessors have not: but Aristotle, far from seeking to destroy their works, has been the chief medium for preserving to us the little which we know about them. His attention to the works of his predecessors is something very unusual among the theorists of the ancient world. His friends Eudêmus and Theophrastus followed his example, in embodying the history of the earlier theories in distinct works of their own, now unfortunately lost.
It is much to be regretted that no scholar has yet employed himself in collecting and editing the fragments of the lost scientific histories of Eudêmus (the Rhodian) and Theophrastus. A new edition of the Commentaries of Simplikius is also greatly wanted: those which exist are both rare and unreadable.