对一段话的理解

Some environmentalists question the prudence of exploiting features of the environment, arguing that there are no economic benefits to be gained from forests, mountains that no longer exist. Many environmentalists claim that because nature has intrinsic value it would be wrong to destroy such features of the environment, even if the economic costs of doing so were outweighed by the economic costs of not doing so.

这段话的意思好像，保护环境可能没有经济上的意义。但环境有其自身价值。我不明白最后一句话。最后一句应该翻译成“毁坏环境的经济代价高于不毁坏环境的经济代价”?outweigh，该怎么理解?