"The modern-minded man, although he believes profoundly in the wisdom of his period, must be presumed to be very modest about his personal powers. His highest hope is to think first what is about to be thought, to say what is about to be said, and to feel what is about to be felt; he has no wish to think better thoughts than his neighbors, to say things showing more insight, or to have emotions which are not those of some fashionable group, but only to be slightly ahead of others in point of time. Quite deliberately he suppresses what is individual in himself for the sake of the admiration of the herd."Correct perception, incorrect analysis. It is not possible for a human being to have a thought which is outside the capacity of humans to have; and if there is an absolute, universal, ontological truth - it must be one that can occur to anyone. Arcane, secret knowledge does not scale.
-- Bertrand Russell, "On Being Modern-Minded," Unpopular Essays
In this case, truth = onto. The fundamental logical equation upon which all nature and humanity is based. The original goal of all philosophy. From the Greek "to on", meaning "that which is". Ontology is the search for the basis of existence, with a view to explain and understand it and not stumble about in the dark. The meaning of life essentially, only not confined to life.
Any thought that an exceptional thinker may have is but one that somebody else would have come upon later (and often enough, somebody has come upon before, but didn't have as good PR). All known philosophy which is in an imperfect sense true, that is, applicable to the perceived world in a useful way, has been created through a titanic effort by the outstanding thinkers of old. But to a modern man who had the benefit of modern schooling, it is self-evident. Both philosophers and students of philosophy like to talk in very complicated phrases - partly for snobbish exclusionism, partly because between two people proficient in the vernacular it really is a more efficient way of sharing ideas. Yet, once you get past all the pretty turn of phrase, the author's point can be summed up in a simple sentence.
Now, humanity's average capability for intelligent thought is not likely to increase very dramatically over time, at least not in the evolutionary blink of an eye we've had to develop philosophy (less than five thousand years); a historical genius, presented with the knowledge base of 2006 AD, would be able to do wonderful things with it.
The point being: any exceptional thought that a genius philosopher may have is inevitably going to be bloody obvious to people living some time after him. Thus it is moronic to suggest that staying ahead of the curve is ignoble. The tidal wave will assimilate you whatever you do. It's just a matter of the interval. Very smart people are far ahead of the surf, marginally above average ones are marginally ahead of it. (And the really smart ones don't get ahead of the surf at all - they point the wave in the right direction.)
Exceptional thought is always self-evident thought expressed before it became self-evident.