Interesting question. There are many things to say here, but just a first remark. As I recall the name Mentor comes from the Odyssey -- the mild-mannered inhabitant of Ithaka, friend of Odysseus, who has agreed to look after things while Odysseus is away. But as far as I remember we never meet the actual person; it's always Athena who appears to us in his guise, suggesting at just the right moment that Telemachus go to Nestor for news of his father, or appearing to give Odysseus support in battle (though I don't recall whether Athena actually fights; as Odysseus recognizes who "Mentor" really is, the simple presence is enough to give him great encouragement). 

I suppose this suggests the following model for mentorship: at critical points a person appears who reminds you, by his or her example or presence, of the extraordinary feats you yourself are capable of; and in return, among all the assembled company who see only the mild-mannered Ithakan man, you alone recognize him for who he truly is, the mask of the goddess Athena. 

Hi George, Solveing,
Your question is a complicated one and I'll just try to say a few comments on it.

1. The political aspect. Mentors, who are many times important people in their field, have also a political aspect in helping their students advance and become prominent. It is not an accident that most successful people had important mentors - yes they help in their development, but also in their career development. This is a less interesting point, and I don't have much more to say about it.

2. Mentors do not have to necessarily be alive. Usually at some point there were some great people in your fields and they are your mentors, alive or dead. For instance Seneca was a mentor to Montaigne, and Aristotle to many philosophers. Moreover, even if your mentor is alive, you might not see him/her as they could be elsewhere, still being someone in your field you admire, you learn from them and consider them your mentor.

Chances are that there is someone in your field, past or present, who you really admire, and who de facto becomes your mentor.

3.  Some people don't have any mentors, and it shows. Many domains are decided by a certain agreement of the field how things are done, and when people come from outside, they don't know the rules, and no matter how good their work is, it will simply be rejected by the field. This point is of course related to the first point.

For instance, even in mathematics, there are many mathematicians working outside of the establishment, without probably any mentor in the field. These people constantly solve the most difficult problemns in the field, and yet are completely ignored. Now, do they really solve them? Well, even in academicmathematics the answer is not so clear. Every once in a while a mathematician of academia will look at one of those proofs, find a fault and move on. But then also mathematicians from the academia, even Fields medalists, constantly also find mistakes in their proofs, many times even after they were verified by other important mathematician. Yes, these people are mostly loonies but who knows. It is simply too much work to take them seriously unless they talk your precise language.

Why this example? To explain that even in a field which seems as absolute as mathematics - either there is a proof or not - even there, speaking the language of the ruling crowd and knowing their habits is mandatory for acceptance, which is all the more so the moment you go to less absolute fields.

4. I don't know about Freud and Einstein, though there are probably people here who know, but I will say that I think originality seems much more original from the otuside than the inside. That is, they see their origins, who they copied from, who they are applying in a different way,  much more than other people do. 

5. Do mentors causing harm? - Very very much, sometimes. The relation of people to their mentors is complicated, and could be quite distructive. Moreover, a lot of mentors don't take kindly to their mentee independence, and react in pathetic ways. They simply can't let them go.

Ok, I'll stop here, though I feel I didn't respond to the more interesting parts of your question, which becomes even more complicated when considering also the arts.

Dear George Mall,

I want to answer in at least two posts, if not more. This is a wonderous set of questions, George Mall!  I am indebted to your spirit and intellect.  I find this avalanche of questions over whelmingly promising of great thoughts and delicious instances to come. I am "stoked" by the inqueries herein, it is a Sees candy box of questions that I can only approach one at a time .I'll attempt to take them one at a time in the order presented for it might help in an eventual clarity that I am not aware of as yet.  But I still must enjoy the  prospect of this lengthy and rich journey before me at this moment. How brightly the sun shines!

1.  Who was Socrates's mentor. I know he had several. I do not recall them but I believe he alludes to their influences . Aside of whom so ever they were, the nature of incephelization (probably not a real word and I am making it up  but you get the drift) was a foot in Greece at the time of Socrates. People were thinking. I am content to think that due to the influx of different cultures that there was a melding due to migrational forces. I doubt that Socrates had ONE person who sparked his mind. I think that he was challenged to incorporate conflicting cultures especially due to his contact with the Persian culture. His mind was set afire by the contrasts of foregn realities like Walt Whitman had been by emigrants to the US. His country men, contemporaries, were stilled in local knowledge,  Socrates had contact with the Persians in his army experiences. So I would say that his war experiences and cultural missigination provided him  the shadow of a mentor.

2. Einstein's and Freud's discoveries would have happened through somebody else if they had not existed. The issues and the science was in the air of growing discourse. The multifacited spheres of knowledge were amongst them, like Kubrick's edifice of 2001 Space Odyssey. It was a societal energy that was created by extant, cultural wealth and emergence from conflict. In short there were thousands of emisaries and thousands of mentors. The operative was interpersonal means of communication as a disembodied mentor. The space provided by: nonguild, non-overseer, non-church, non-state existence was the enviornment that allowed their freedom of conceptualization. It is interesting to note that all these people were fairly poor. They lived below the radar of the establishments they served. They were not wealthy land owners or operators of finance. They were not "contributers" to their society. Just look at them. So much for the glorious promise of capitalism. Creativity happens despite capitalism not because of it.

3. Does everyone need a mentor? No. But everybody could benefit from one.
4. Is there a process to finding your own appropriate mentor? Yes. But here I am constrained and conflicted. There is a conflict for me here because I am seeking a mentor here on THINQon. I've identified her. I know her. She is the other half of myself, our values are the same and our needs are quite different. She has even suggested this very question, off hand like, as though it were simply like taking a pair off of a shelf and so I must stop because I am ...... cross-tendered .. conflicted .. impossibly nuanced by attraction...in wonderful love ... and confused for a while. I must think by myself because I don't want to confuse what I want with the means of attracting it. I am silenced by my confusion, what one would call a conflict of interest.