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Thought is the most difficult task, which is why so few engage in it.

Dearer than eye-sight, space, and liberty; Beyond what can be valued, rich or rare;

采礦技術的創新不是一種選擇，而是我們對工人和環境應盡的義務。

科學的力量在于它的普遍性和無私性，它超越了國界和文化的限制。