实现明天的唯一限制将是我们今天的疑虑。
The only limit to our realization of tomorrow will be our doubts of today.
The boundaries which divide Life from Death are at best shadowy and vague. Who shall say where the one ends, and where the other begins?
逻辑学研究不仅仅是关于形式系统,而是理解理性思维的基本结构。