Ethical theories can be viewed in different ways and ethical thinkers sometimes have writings which suggest different kinds of ethical thinking.
Situation ethics is quite often called relativist. In fact it is classified as an example of a relativist theory by exam boards and some books. This is not surprising. Situation ethics does not propose definite instructions on right and wrong actions. It is not deontological. Situationism prefers to decide the right and wrong thing according to what is believed to be the most loving thing to do in the particular situation. So the right thing to do is relative to the situation, hence the idea that Situationism is relativistic. This point was made by Joseph Fletcher’s critics. And yet there is an aspect of Situationism which is not flexible and that is the principle of doing the thing that will bring about the most loving end. The principle is not flexible in the same way the principle in utilitarianism is not flexible. That principle suggests the right thing to do is that which brings about the greatest good for the greatest number. So the principle can be a fixed principle – an absolute, while the actions classified as right or wrong vary depending upon what is indicated in the principle and the Situation that the principle is being applied.

Sometimes our tendency to want to put things into tidy categories can also distort how we see a Philosopher. Thomas Aquinas, for instance, is usually associated with natural law and ‘categorised’ as a deontological thinker. Natural law is based on an idea of what it means to be human and the main ways of living that are good for a human. These ways must be followed and so indicate that some actions are good and others bad, depending on whether they support the idea of what it means to be human. However, that is not the only thing that Aquinas thought about moral decision making. When considering war he did not follow this approach precisely. He could have applied natural law to war and concluded that the taking of life is wrong because it opposed the life of human beings. Aquinas notes this but goes onto write about the just war theory which involves a degree of proportionality. Aquinas supports the idea that war can be just if it is by the command of the authority of the sovereign by whose command the war is to be waged, if it is being fought for a just cause and if the intention behind the war is for the advancement of good, or the avoidance of evil. So those who wage war justly aim at peace. Here, Aquinas is taking account of certain external factors, other than the action of killing itself. So he is not being strictly deontological in every action in this case, because he recognizes that there are greater interests in wars which better protect human nature. It is because of this that Aquinas may be interpreted as being a bit more flexible than otherwise thought. Particular situations may require different actions at different times. There is also his writing on conscience and how that might relate to natural law and just war theory. It is not surprising that one of the most brilliant thinkers and writers in Western philosophy and theology should make so many contributions to ethical thinking.
These two examples serve as a warning to be careful about how we categorise theories and thinkers and explain partly why there are so many different views of the people and their ideas.