This fact is not surprising given the lighthouse top of his thinking, as we can see from some of his writing, is at this study area. However, the actual claim of Al-Ghazali's ideas penetrated widely into a variety of other scientific branches, such as fiqh, usul fiqh, kalam, ethics, and even economics. Thus, al-Ghazali is not only good at talking about Islamic philosophy and mysticism, but he was also an expert review of economic questions, particularly about the ethics of Islamic finance.

Nejatullah Muhammad Siddiqi in his book Reading in Islamic Economic Though entering the name of al-Ghazali to the rows of the Islamic economic thinkers second phase together with Ibn Taymiyya, Ibn Khaldun and other figures. In the second phase of this discourse of Islamic economic thought has developed an intensive and are characterized by changes in the power structure of Islam is increasingly widespread.

The style of Islamic economic thought during this time is more focused on micro-economic analysis and the functions of money. Al-Ghazali, for example, a lot of money mentioned, function, and evolution of its use. He also explained the problem prohibition of usury and its impact on the economy of a nation.

Indirectly, he discussed the problem scales, price controls (at-tas'is or intervention), the determination of tax in certain circumstances or emergencies. He also talked about how to overcome the impact of price increases, whether the market mechanism or government intervention, and others.

Bernand Lewis (1993) asserted that the concept of Al-Ghazali's finances shows the typical character, given the philosophical nuances kentalnya base due to the influence of mystical science. However, the interesting part of the financial outlook is that Al-Ghazali was not trapped in a philosophical plateau, but shows a harmonious mix between This real condition that occurs in people with philosophical values are accompanied by a logical argument and clear.

Therefore, for the financial outlook of Al-Ghazali's neat that it becomes an established concept, this short article to describe fully the financial outlook around him to then be reviewed in the perspective of the Islamic economic system.

The concept of money
In his landmark work, Ihya 'Ulum ad-Din, al-Ghazali defines that money is the goods or objects that serve as a means to obtain other goods. The body is regarded not as an item value (intrinsic value). Therefore, he likens the money as a mirror that does not have their own color, but can reflect all kinds of colors.

Refer to these criteria, in terms of defining the money, he not only emphasizes the aspects of the functions of money. Such a definition is more perfect than the limits set out most of the more conventional economists define money was limited to the functions inherent in money itself.

Because the money according to Al-Ghazali only as a standard price of goods or things then money has no intrinsic value. Or more precisely the intrinsic value of a currency that is shown by his real existence, there has never been considered. Al-Ghazali's assumption that money has no intrinsic value is ultimately related to the issues surrounding the demand for money, usury, and selling currencies.

First, the ban hoarding money (hoarding money). In the Islamic concept, money is the public body which has a significant role in the economy. Therefore, when the money withdrawn from circulation, will lose an important function in it. For that, the practice of hoarding money is strictly prohibited in Islam because the instability will affect the economy of a society.

According to Al-Ghazali's basic reason for the prohibition of hoarding cash because such action would eliminate the inherent function of money. As mentioned, the purpose is to make money circulating in the community as a means of transaction and not to be monopolized by certain groups. In fact, the worst effects of the practice of hoarding money is inflation.

In this case economic theory explains that the amount of money in circulation and the amount of goods available at the same time close relations inversely. If the money supply exceeds the amount of goods available, there will be inflation.

Conversely, if the money supply less than the goods that are available there will be deflation. Both the economic disease that must be avoided so that between the money supply of available goods in the market balance.

Second, the problem of usury. In a simple addition of riba is the subject of capital obtained by way of falsehood. Explicit prohibition of usury in the Qur'an Surat Al-Baqarah verse 275, 278-279, Ar-Rum 29, An-Nisa '160-161, and Ali Imran 130. Fundamental reason Al-Ghazali in the forbidden usury related to money is based on the motifs printed money itself, that is, only as a medium of exchange and standard of value of goods only, not as a commodity. Therefore, the act of riba by way of exchange of the kind of money is the action that came out of the original purpose of creation of money and prohibited by religion.

Third, buying and selling currencies. One of the things that belong in the category of riba is the buying and selling currencies. In this case, Al-Ghazali thus prohibiting this practice. For him, if the practice of currency trading is allowed the same as letting someone else make money hoarding practices will result in a scarcity of money in society. Since the sale, the money will only be circulated in certain circles, namely the rich. This action is very unjust.

So a bit of the financial outlook of Al-Ghazali is filled with the spirit of universal humanity and the Islamic business ethics. However to become an established concept and perfect, the thought of Al-Ghazali's finances are still scattered They require hard work from his heirs for later re reconstruct systematically and logically.