"The Neapolitan Administration defines common goods as “the tangible and intangible assets of collective belonging that are managed in a shared, participatory process and which is committed to ensuring the collective enjoyment of common goods and their preservation for the benefit of future generations.” (http://politicalcritique.org/world/2017/naples-common-good-empty-buildings/)
"What are we talking about when we refer to ‘common goods’? We are talking about goods and resources that, rather than being bound by ideas of property or belonging, assume by their own natural and economic vocation functions of social interest, serving the interest not of public administration but those of a given collectivity and the people who make it up. And so, common goods require a different rationale to the one that has dominated the economic, social and political debate for so long. We refer here to the binary logic that always forced us to choose between public and private property. In the case of commons, the direct relation between common goods and the people making up the totality tells us what needs there are and what are the necessary goods for satisfying them, thus modifying the juridical conception that has held up structures of property since the establishment of Roman law. People have needs that are not met by the rigidity implied by property structures. We are not talking about just another type of property: this is the very opposite of property, the non-transmissibility of common goods being a key element in the debate." (http://www.opendemocracy.net/joan-subirats/commons-beyond-market-vs-state-dilemma)
Common Goods and the non-individualistic view of the world
"The ‘tragedy of the commons’, as Ugo Mattei has recently pointed out, throws into relief two contradictory positions held today.
Hegemonic representation, essentially founded on social Darwinism, holds up competition, conflict and emulation as the essential triad of reality. That conception grew out of a ‘modernisation of the progress’ of market forces that leant on public political institutions. This is how communal goods and communal life were atomised, colonised and brought to an end.
At the other extreme, we have a holistic and ecological view of the world, based on relationships of reciprocity, cooperation and community. \
The commons breaks with the individualistic vision as conceived by the capitalist tradition, a vision that has progressively transferred the idea of rights to individual people. The commons take inclusion and everyone’s equal right to access as its starting point, while property and the idea of the state that upholds it is based on a rivalry of goods, and thus on exclusion and concentration of power in institutions that insure and protect it. The commons try to situate themselves outside the subject-object reductionism that would lead to their commodification. The commons cannot be commodified (because they cannot be transferred, or alienated), and they cannot be the object of individualised possession. And so they express a qualitative logic, not a quantitative one. We do not ‘have’ a common good, we ‘form part of’ the common good, in that we form part of an ecosystem, of a system of relations in an urban or rural environment; the subject is part of the object. Common goods are inseparably united, and they unite people as well as communities and the ecosystem itself.
For many years there has been tension and conflict between private and state methods for managing collective assets. The great struggles of the industrial era of the nineteenth and twentieth centuries were couched in this dichotomy, which inspired but was also nourished by ideologies that argued for decades about the greater efficiency or greater justice enshrined in various formulae for social, economic and thus political organisation. We are talking here of the ‘commons’, of what is commonly held, and that refers to spaces, themes and initiatives that have their own boundaries, their own social rules for use, norms for punishing or dissuading ‘free riders’ who only want to profit from the commons. When we talk about the commons, we must invariably refer to the community and the relationships that sustain and run it.
The experiences that Ostrom and others have systematised and analysed show the importance of the structures or institutions that can manage common goods, reinforce interdependencies and dissuade those who want to take advantage of them opportunistically. The key is the capacity of common goods to reinforce interdependencies, the advantages of sharing, of feeling involved (which does not always arise in the case of public goods) and reduce the temptation to outsource costs (an aspect that characterises private goods). The more articulation and reinforcing of interdependencies there can be, the more aware people will be of the advantages of sharing, and the weaker will be the tendencies to segregate and to outsource costs." (http://www.opendemocracy.net/joan-subirats/commons-beyond-market-vs-state-dilemma)
Common Goods in Economics
One of the most common ways of looking at goods in economics, illustrated in the table below, is the classic division based on:
- whether there is competition involved in obtaining a given good
- whether it is possible to exclude a person from consumption of a given good
For the table see here 
The goods referred to as common pool resources are also known as common goods.