Ecological economics is a trans-disciplinary field. It’s not trying to become sub discipline of economics or even a sub discipline associated with ecology, but it is just a bridge across not only ecology and economics but psychology, anthropology, archaeology, in addition to history. That’s what’s necessary to obtain a more integrated picture of how humans have interacted using environment during the past and how they could interact sometime soon. It’s an attempt to consider humans embedded into their ecological life-support system, not separate on the environment.