Woooooowwww haha.
Grammar, is a friend.
And don't be so needy, asking for answers right away doesn't change when people will give them to you haha. And on to the answer.
Thomas Malthus proposed that overpopulation is a problem, and would be the fall of mankind. Many people have taken this view point, and have made many many many predictions about running out of a certain resource such as food or oil and have all been wrong in the past. The mathematics they used may have been right, but didn't account for the beautiful human greed that gives us such a wonderful opportunities and lifestyles.
The theory of Thomas Malthus can only have an impact on politics really. The biggest factor in a change of the purchasing patterns of society as a whole is a change in the prices of goods. If we were running out of a substance, the price would go up in anticipation of the shortage and people would begin ration due to prices. It wouldn't matter if they knew or even cared about an upcoming shortage. All they have to know is the price has gone up and that is all that they do need to know.
Now onto the human greed aspect. If a shortage of any resources was eminent, than the price would be going through the roof. Lets take food for example. Lets say food was going to run out. Lets say you are a 'evil and greedy capitalist' (can't help but hate them haha) and all you care about is making money. Than the best way to make money, a way to get filthy rich beyond all your dreams would be to find a way to increase the production of food and save the world from starvation and famine. Yes, that person may be evil, and I may have very little respect for such a person, but it was that very greed which saved us. In a capitalistic society, greed is captured, and used to benefit society.