Resources are limited?

As a student of economics, I was always told that resources are limited and our needs are unlimited,and the shameful point to be noted is that this is the base of economics, In reality, according to me human wants are limited and resources are unlimited.Mahatma Gandhi truly says that “MOTHER EARTH IS CAPABLE TO FULFILL NEED OF EACH AND EVERY PEOPLE, BUT NOT THE GREED.” but human being is not greedy by nature.its result of scarcity but when you know that there is no scarcity at all than your behavior might be Chang.It simply means that greediness is human behavior not human nature.so we can says that resources are more than enough than our need,and here is the proof ........

Earth has a surface area of 196,940,400 square miles, slightly less than a perfect ball with a diameter of 7913.5 miles (which is the mean diameter of the Earth).
The surface area of the seven continents and all the islands of the world is about 57 million miles, while the total area of the six habitable continents (Antarctica excluded) is around 52 million square miles.
Including Antarctica, over one fifth of the globe's land mass is under water (oceans, lakes, rivers, etc.) or ice. This leaves about 45 million square miles of exposed land.
The human population on earth has crossed six billion. If we distribute all the exposed land evenly among all mankind, 133 people would have to share one square mile. What that means is that every single person on Earth, man woman and child would have close to five acres of land for his or her use. More precisely, each person would get 209,000 square feet of land, or a square plot of land 457 feet on each side.
Not all this land can be used beneficially however. A significant portion of the Earth's exposed land is uninhabitable or cannot be used for any agricultural purpose. Large portions lie in the far north. Large portions are extremely arid. Large portions are very mountainous. In sum, only about one fourth of all the land on earth, or somewhat more than 12 million square miles, is arable.
Today, over half of the arable land in the world is in fact not under cultivation. Bringing the unused land into service in many cases would require huge investments of money and effort, and would do considerable damage to the environment. For example, only about 28% of the arable land on the African continent is used for growing crops. Immense tracts of forests or jungles would have to be cleared to bring the rest of the arable land on that continent to productive use.
Thus, only about one eighth of each imaginary plot of land distributed to each person is land which is under cultivation. In effect, each person has a piece of land about 26,000 square feet (a square 161 feet on each side or just a bit more than ½ an acre) at his or her disposal on which to grow all that he or she needs.