Introduction Plato, the philosopher, was the first to work on the subject of idealism. Idealism deals with what constitutes a perfect human being, viewing him as one who contains both spiritual and material characteristics. Of the two, spiritual is considered the most important human aspect because it focuses on the mind and character but not the physical human body. On the other hand, realism is thought to have risen towards the end of 19 th century. It is often applied in different areas such as arts, international relations, law, among others. This paper views realism as used in the last two areas, international relations and law. It is more of a thinking that focuses on the security of a country. It is naturally imaginary implying that it is made by man, and thus contains errors because man is well known in creating mistakes. Realism theories range from classical, liberal, legal, to mention a few. The two, idealism and realism operate under certain principles. The following paragraphs deal with the basic principles of each. Basic principles of idealism A major principle in this philosophy holds that there is a mind powerful than that of human beings. It is often called the principle of universal mind. It is believed that there is a special man, greater than human beings, whose ability of thinking is better than that of all men. The principle holds that this special person is invisible but has the power to influence the minds of human beings and that is why the principle views this special person as God, who creates people, gives them life and their present minds that help them think. The other principle views people as being holy. It says that the strength of the minds of people is greater by far compared to other animals. Basing on this, it constitutes the most important aspect of life, making people special than all other animals. This philosophy is also built on the principle of the advantage of information and standards. It claims that people have more advantages compared to animals. They have a superior knowledge of things than animals. This is thought as a gift from God whom they believe exists and gives them the desires of their hearts including their desire of knowledge. The other idealism principle says that real things originate from the mind and not from the common senses of people. It holds that the ability of people to think is what enables them make real things. Real things do not come by seeing, hearing, feeling, but through thinking. Basic principles of realism “ Realism assumes that interest defined as power is an objective category which is universally valid but not with a meaning that is fixed once and for all. Power is the control of man over man “(Hans 7). One of these principles says that people are ruled by laws that are made by other people but not God. This philosophy includes the principle that people should be respected in terms of their powers or academic knowledge. Therefore, the more educated or the more powerful a person is, in politics, the more respected he/she becomes. Realism considers the lessons learned from politics enabling it to know what to and not to do in order for a nation to succeed politically. The principle of identity used in realism says that the laws governing a