1.
No intelligent man believes that anybody ever willingly errs or willingly does base and evil deeds; they are well aware that all who do base and evil things do them unwillingly.
Protagoras
2.
Man is the measure of all things.
Protagoras
3.
Man is the measure of all things, of the reality of those which are, and of the unreality of those which are not.
Protagoras
4.
As to the gods, I have no means of knowing either that they exist or do not exist.
Protagoras
5.
Many things prevent knowledge, including the obscurity of the subject and the brevity of human life
Protagoras
6.
Concerning the gods, I have no means of knowing either that they exist or that they do not exist, nor what sort of form they may have; there are many reasons why knowledge on this subject is not possible, owing to the lack of evidence and the shortness of human life.
Protagoras
7.
There are two sides to every question.
Protagoras
8.
About the gods I have no means of knowing either that they exist or that they do not exist or what they are to look at. Many things prevent my knowing. Among others, the fact that they are never seen.
Protagoras
9.
Everyone, including the Athenians [...] are right to accept advice from anyone, since it is incumbent on everyone to share in that sort of excellence, or else there can be no city at all.
Protagoras
10.
Man is the measure of all things, of things that are that they are, and of things that are not that they are not.
Protagoras
11.
When it comes to consideration of how to do well in running the city, which must proceed entirely through justice and soundness of mind.
Protagoras
12.
There are intelligible principles inherent in the matter of every phenomenon; because matter is essentially the sum of all the seemings that it has for any and all persons.
Protagoras
13.
As touching the gods, I do not know whether they exist or not, nor how they are featured; for there is much to prevent our knowing: the obscurity of the subject and the brevity of human life.
Protagoras