One difficulty is that almost all of what is called behavioral science continues to trace behavior to states of mind, feelings, traits of character, human nature, and so on.
本句译文：
难题之一在于所谓的行为科学几乎全都依然从心态、情感、性格特征、人性等方面去寻找行为的根源。
句子透析：
第一、句子可以拆分为两段：One difficulty is that almost all of what is called behavioral science /
continues to trace behavior to states of mind, feelings, traits of character, human nature, and so on.
第二、句子的结构是：
1)主干结构是表语从句One difficulty is that...
2)almost all of what is
called behavioral science
是表语从句中的主语部分，后面是简单的谓语和宾语结构。
今日句子重点词汇：
continues to trace behavior to继续针对……研究行为
behavioral science 行为科学
states of mind 心态，意识状态
feelings 感情
traits of character 性格特点
今日赠言：
不放弃任何一次学习进步的机会
你将最终取得理想的成功！
Never give up any opportunity of making progress in study,you will eventually succeed.
