Answer: It is necessary to say that Islam's perspective greatly differs with the perspective of socialism and capitalism regarding the private and public ownership. As a general rule, Capitalism believes in private (personal) ownership and accepts "the common ownership" in special conditions of social needs. In contrast to Capitalism, we have the Socialism which believes the common ownership as a general rule.
It never accepts the private ownership unless in excepted cases. Among these, the economic school of Islam believes in the private ownership as a gift from God who is the owner of the entire universe. It also has the same concept for the common ownership.
In summary,
1- the private ownership in Islam is distinguished and confirmed as a fact,
2- developing and extending properties is done in two ways; in one way, if the goal of increasing the richness is to supply the essential needs of life, to preserve face, to give good service to others and to do good deeds, it will be strongly encouraged but if the goal of increasing richness is the pleasure, lust and other things, it will be discouraged in Islam. Imam Ali states,
“In gaining the trivial things of this world, they go faster than each other and begin to struggle on a dead body”.
3- As well as the attention to the spiritual development, Islam focuses on the development of economic fields, since the spirituality and materiality are along with each other. The culture and spirituality of a society can provide the welfare and economic growth of that society. This economic growth also can be an appropriate field for mankind's spiritual characterization.
4- Considering the previous facts, it can be proved that man's growth and prosperity is not only summarized in the economic issues, but it can be regarded as one of the basic elements of man's spirituality. Therefore, gaining the rich is not considered as an appropriate condition for personal and common welfare but certainly is regarded as a necessary condition.