The greatest threat to our forests is not the axe, but indifference.
对我们森林的最大威胁不是斧头，而是冷漠。
The truth is, the science of Nature has been already too long made only a work of the brain and the fancy: It is now high time that it should return to the plainness and soundness of observations on material and obvious things.
当你无法回头时，你只能担心如何向前迈出最佳的一步。