an eminent Greek philosopher of the Eleatic school, was born at Elea in Magna Graecia in the latter half of the sixth century B.C. The history of his education is not very well ascertained. Report speaks of two Pythagoreans, Ameinias and Diocletius, as his instructors. He is also said, with less verisimilitude, to have been a disciple of Xenophanes, the founder of the school of Elea. At all events, it is certain that he studied with great success, and rose to a high place in the estimation of his countrymen. He was honoured to be the instructor of Empedocles and Zeno; Plato surnamed him "the Great," and likened him to Homer; Aristotle considered him the chief of the Eleatics; and his own fellow-citizens were wont every year to swear obedience to a code of laws which he had laid down. The main philosophical opinions of Parmenides have come down to us in some fragments of a hexameter poem, entitled On Nature. They may be represented in the following short outline:—Assuming that sense and intellect are the only two sources of knowledge, he holds that these furnish the mind with two kinds of ideas entirely distinct. Sense is dependent on the variable organization of the individual; and therefore its evidence is changeable, false, and nothing else but a mere appearance. Intellect is the same in all individuals; and therefore its evidence is constant, true, and a complete reality. The subject is thus divided into two branches—physics and metaphysics; the former inquiring, What is the character of appearance? and the latter, What is the character of reality or being? Metaphysics, or the science of being, is discussed in the first of the two books of the poem. Being, it is asserted, is eternal. For if it be non-eternal, it must either have sprung out of being or non-being. It cannot have sprung out of being, since it cannot precede itself; and it cannot have sprung out of non-being, since non-being is utterly inconceivable. It is therefore eternal. Being is also identical with thought. For as it is eternal, it must be unchangeable, identical, unique, unity itself. Since it is unity, it must embrace all objects, and consequently all the thoughts that are occasioned by these objects. Being is therefore identical with thought. After the first book of the poem has thus evolved an ideal system of metaphysics, the second book proceeds to treat of the science of appearances or physics. A fanciful theory of the physical world is then laid down in accordance with the principles of the natural philosophy of that day. The most complete collection of the fragments of Parmenides is that of S. Karsten in the Philosophorum Graecorum Veterum Operum Reliquiae, 8vo, Amsterdam, 1835.