Ancient Philosophy - Parmenides, Heraclitus, Zeno, Eleatic

The History of Ancient Philosophy

Parmenides’ position begins with the statement that “What is is and what is not is not” and that these two statements are mutually exclusive and not interchangeable. So something that is must always be, it can never perish or change because then it will become what “is not”. He believes that something that “is not” is unintelligible and that only things that can be thought of are real and only real things can be thought of. Therefore for something to pass into the realm of not being then it can no longer be thought of and is not considered real.

By the same reasoning things must never have had a starting point because that would imply that before that point it did not exist and therefore it was and is not real. He takes this idea even further to say that nothing has a past or a future. Even the immediate past and future do not exist because it means there was change. For Parmenides change means that something has passed from being one thing to another and therefore is not that original thing, and will soon change into something else. This constant change that we see every day does not actually happen and cannot be considered real. All things must be the way they are now and have always been and will be. Parmenides idea of the universe was one that was completely unchanging with one beginning or end and nothing like time or motion. With the same logic he argued that the world cannot consist of many things. If I have a desk and an apple then I can say that the desk is not the apple and the apple is not the desk.

Since it is impossible to think of something that is not then there must not be and apple or a desk. Parmenides believed that the universe is completely whole and one. He envisioned the universe as a sphere completely solid with no room for motion or ability for change. All the things that we see and the changes that we sense are not real, only this one sphere is real.
Zeno does not directly argue the ideas of Parmenides but instead uses tricks with math and infinity to attack plurality and motion. The first is about Achilles and a turtle. Achilles and a turtle are going to run a race. Let us say the Achilles runs ten times as fast as the turtle and the turtle gets a tem meter head start. While Achilles runs the first ten meters the turtle runs 1/10 of a meter. Achilles then runs 1/10 of a meter but the turtle pulls ahead 1/100 of a meter. This continues forever and Achilles can never win the race. This is supposed to prove an apparent paradox in the concept of motion. Another is about men in a stadium.

If one line of men is standing still and two more line pass on one side parallel and in opposite directions that it would seem that a man in the middle line is passing one man in the still line and he passed two in the moving line. Zeno says that it is impossible for a man to be passing both one man and two men at the same time. Again he is remarking on the paradox of what we perceive as motion. The flaws in both these arguments are apparent with a little thought. In the first argument he is simply playing with numbers. You can take any number and divide it into parts indefinitely, but if you gave real values to the speeds of Achilles and the turtle you would immediately see the expected outcome of Achilles victory. The second argument falsely assumes that the fact that the third row of men is moving does not matter.
Parmenides touched on some truths even if it was unintentional. His original statement of what is is and what is not is not seems strait foreword and obvious. Thing either exist or they don’t. His next step I quite a leap though. The idea that just because something is it can never not be or not have been. We see some quality of this in the idea that matter is never created or destroyed, he may have been on the right track even though his idea was false. His ideas on change however are completely wrong. Change does not necessarily mean something no longer exists. Since matter is never created or destroyed then the way we get new things is through change. Our world is in a constant state of change. These two miss representations of realty make for a very odd view of the universe. The idea that everything we see is an illusion and that the universe is one and unchanging are obvious falsehoods.

Heraclitus’ philosophy was fundamentally different from that of Parmenides. First off Heraclitus has a very mythological point of view. He borrows heavily from culture and traditions while adding his own ideas. He talks of the four elements and their struggle. He gives the cosmos very human qualities. Heraclitus speaks of logos, which is the basic order of things, and Parmenides speaks of the oneness of the universe which is somewhat of a similarity. Parmenides’ point of view is much more scientific. He uses logic and reason to draw conclusions from truths. Even though the conclusions that the Eleatic philosophers reached were wrong I think it is their methods that have had a lasting influence.

Before them philosophy was mainly in the realm of the mythological. People would make statement explaining nature in abstract ways. The Eleatic philosophers tried to use reason to determine truth. I think reason survived because although it did not work for them it certainly does work now. The more knowledge we have the easier it becomes to use reason and logic to seek truth. It is also easier to argue for and harder to argue against a reasonable and logical point. This is very different from the philosophy of someone like Heraclitus which requires faith to believe in their point of view.

[HARRY256]

First of all Achilles was not a philosopher nor he knew or said anything about it.
Achilles was a warrior.
Moderate your title please.

Secondly, Philosophy comes from Philos + Sophia which means friend of wisdom.
There are many and much more great philosophers than the ones you posted.
For example, Socrates!

Not only the so called "Philosophers" were making thoughts of the world but also many historians like Aristophanes, Herodotus, and many more which are considered great idealists just by writting their thoughts on the events!