True courage is not the absence of fear, but moving forward despite it.
一个奇怪的事实是,根据从生物学或地球物理学的角度出发,对地球史前条件会得出完全相反的结论,这反映了我们目前知识的不完整状态。
"Always be transparent about the limitations of your study."
The periodic table is a testament to human curiosity and ingenuity.