Humanism In Writing

Reading the first chapter of The Great Gatsby re sparked my interest in the writing of psychology. Yes, you read that correctly, the writing of psychology. It's my personal opinion that an author's ability to break down and compose the human condition, at least when dealing with characters, is the most important factor in creating compelling prose.
This is not an easy thing to do however. Writing about the inner workings and motivations of characters' is tricky. The writer runs the risk of applying too many of their own idiosyncracies into the writing. Having a strange or abnormal way of viewing things, though creative when executed correctly, can alienate the reader and dislodge them from the world the author is trying to pull them into.
It's also important not to be too convoluted in your interpretations of humanism. It's rarely a good idea to fill your writing with complex ideas related to a characters psyche or motivations. it detracts from the potential deepness of the plot.