It is an essay based on a hypothesis (an educated guess). It is based on a reasonable possibility that has not yet been proven in fact or testing but seem to give a logical explanation.
This is the kind of essay which is aimed to state some hypothetic course of events. It is usually based or real scientific proves which makes this essay a non-fictional one. If you need to see some examples or if you find it difficult to write it on your own, you may visit Supreme-Essays to assist you.
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