In the short time that I have been supervising undergraduates I have discovered that there is a widely-felt desire to make a personal policy statement in the final paragraph of an essay, regardless of the essay title; people like to end an essay with a sweeping personal manifesto about the way to solve all the problems of science, philosophy, ethics, politics, and theology.
There are two particularly popular personal manifestos: Relativism and Mysticism.
The mystic, on the other hand, believes in the absolute ineffability and indescribability of the divine; he might say something like:
There are two points that I want to make about the final paragraph of an essay. First, it should not contain a personal manifesto; rather it should contain a summary of the way that you have approached the question and a clear statement of your answer to the question. ALWAYS ANSWER THE QUESTION. If you do not answer the question your mark for an essay will go down at least a whole class in the exam. Your conclusion should do two main things: first, it should recapitulate and summarise what you have said – naming the most important arguments and examples; secondly, it should provide a clear synthetic statement of your position – the position for which the arguments and examples you have just summarised are providing support – which should be a direct response to the question/title of the essay. It is sometimes a good idea to repeat the question at the start of your last paragraph.
Secondly, both the relativist and the mystical manifestos, especially in their most stark and extreme forms, are unsatisfactory positions to take when writing an academic essay. The reason for this is that they are both ways of avoiding actually producing and evaluating the arguments for and against a particular position.
It is not good enough to say that it just depends what you think or that ultimately we cannot know anything. In an academic essay you are required to analyse the arguments and the evidence put forward by various different people and explain why you think that one position is more or less reasonable and persuasive than another position. It is not true that all positions are equally valid; nor is it true that all philosophy and theology is impossible because of the limits of human reason.