Nice one...it definitely sounds familiar. Such a quote could have several sources. For some reason it sounds like something from one of Socrates works, such as "The Republic", but that's obviously not it. I'll have to do a little hunting thru my library it seems. It could be a variation from the Dao De Jing, but unlikely with the usage of 'conforming to reason' it has a more Confucian ring to it.
As far as the meaning of the quote goes, my own personal interpretation is that if one sacrifices his/her own belief/feeling on a matter to someone elses reasoning, he/she ultimately gives up a part of themselves to others. Thus, in a sense, going against the natural course that they should have followed if they had 'listened' to their own instincts.
Of course, I'm probable way off from the actual interpretation, but I choose to listen and follow my own instincts on this, so technically, I can't be 'wrong' in the traditional sense.
Back to you for your verdict/execution Kusojiji
All streams flow to the sea because it is lower than they are. Humility gives it its power.