For a person who is not spiritual, respective needs and aspirations may be unlimited. In the materialistic world, sustainability means continuity of the ongoing practices and use of products. The practices and products change in space and time, so the definition of sustainability changes.
The spirituality of an individual helps in achieving materialistic sustainability. That is, a spiritual person is always content and uses bare minimum materials.
All the essential things like food, water and air help form a physical body. None of the other physical assets and money that one possesses can enter into one’s physical body. They can just be a part of memory. We find people saying something like ‘I have so many assets or money or degrees or resources or the support of others etc.’, this is a kind of the state of human beings mind, which tries to be happy with the thought of possessing the capitals for a sustainable livelihood. The livelihood assets include the capitals, they are social, human, physical, natural and financial. One may have more or less of these capitals, but spiritual capital, which is also a part of Human Capital, only makes a person lead a complete and awesome life.
Human mind guides one’s actions and provides a kind of meaning and identity to one’s being. These ideas and acts, in fact, are mostly the greed or creating securities for an uncertain future. This is driving some of the humans in their rat-race for materialistic goals. This is the reality and it is only a matter one is after, which is never a part of the inner being of a human. So this realisation should exist among all humans. Once they start realising these basic things then the whole world and all humanity will be more concerned and will be working for the common good. Human needs and greed is the cause of negative environmental changes. The environmental impacts are irrelevant if there is harmony among all life on this earth. A spiritual person improves environmental conditions.