Aristotle's Theory of the Soul in De Anima focuses on the types of soul possessed by different types of living beings, distinguished by their different operations. He holds that the soul is the form, or essence of any living being; that it is not a substance distinct from the body in which it is found; that it is the possession of a soul (of a specific type) that makes an organism an organism, and therefore that the notion of a body without a soul, or a soul in the wrong body type, is simply incomprehensible. Aristotle uses his familiar matter/form distinction to answer the question “What is the soul?” says that there are three types of substance which are matter, form and the composite of matter and form. Aristotle is interested in living compounds. These - plants and animals - are the things that have a soul. Their souls are what make them living beings. Aristotle also argues that the mind is immaterial, capable of existing without the body, and immortal saying "To say that something has a soul simply means that it is alive." Meanwhile, Aristotle's hylomorphism is needed here, as he would like to be able to explain how living things are generated, change and grow. “For Aristotle the question is this. Matter can take on new forms, some of which are accidental while others are essential." It is clear from this quote that Aristotle means something very different by his use of the Forms. While Plato believed that the Forms were universal truths that can only be truly known by the immortal soul, Aristotle believed that the Forms were completely knowable through investigation unlike Plato's theory, "which sees individual things in this world as in participants in some way in the immutable world of Forms". , has difficulty explaining how what... middle of paper......of the body, and does not pose any problem about how soul and body can unite in a substantial whole: "there is no need to investigate whether the soul and the body are one, no more than the wax and the form, or in general the matter of each thing and that of which it is the matter; for while "one" and "being" are said in many ways, the primary [sense] is actuality" (De anima 2.1, 12B6-9). Many twentieth-century philosophers have sought just such a middle ground between materialism and dualism, at least as far as the human mind is concerned; and much scholarly attention has been directed at the question of whether Aristotle's vision can be aligned with any of the modern alternatives, or whether it offers something preferable to any of the modern alternatives, or whether it is thus tied to a falsified Aristotelian science unfortunately having to be liquidated as it is no longer an active option.