According to the anthropologists, there is nature's law of struggle for existence and survival of the fittest. But they do not know that behind the law of nature, there is the supreme direction of the Supreme Lord Personality of Godhead.

731203SB.LA                  Lectures
Prabhupada: Now read the purport also.
Pradyumna: "According to the anthropologists, there is nature's law of struggle for existence and survival of the fittest. But they do not know that behind the law of nature, there is the supreme direction of the Supreme Lord Personality of Godhead. In the Bhagavad-gita it is confirmed that the law of nature is executed under the direction of the Lord. Whenever therefore there is peace in the world, it must be known that it is due to the good will of the Lord, and whenever there is upheaval in the world, it is also due to the supreme will of the Lord. Not a blade of grass moves without the will of the Lord. Whenever, therefore, there is disobedience of the established rules enacted by the Lord, there is war between men and nations. The surest way to the path of peace is, therefore, dovetailing everything to the established rule of the Lord. The established rule is that whatever we do, whatever we eat, whatever we sacrifice, whatever we give in charity, must be done to the full satisfaction of the Lord. No one should do anything, eat anything, sacrifice anything, or give anything in charity against the will of the Lord. Discretion is the better part of valor, and one must learn how to discriminate between actions which may be pleasing to the Lord and those which may not be pleasing to the Lord. An action is thus judged by the Lord's pleasure or displeasure. There is no room for personal whims. We must always be guided by the pleasure of the Lord. Such action is called yoga-karmasu kausalam, or actions performed which are linked with the Supreme Lord. That is the art of doing a thing perfectly."