Aristotle refutes Plato’s Theory of Ideas on three basic grounds: that the existence of Ideas contradicts itself by denying the possibility of negations; that his illustrations of Ideas are merely empty metaphors; and that the theory uses impermanent abstractions to create examples of perception. Though the theory is meant to establish concrete standards for the knowledge of reality, Aristotle considers it fraught with inconsistencies and believes that the concept of reality depends upon all forms’ correlation to other elements. Ideas, Plato believes, are permanent, self-contained absolutes, which answered to each item of exact knowledge attained through human thought. Also, Ideas are in Plato’s view concrete standards by which all human endeavor can be judged, for the hierarchy of all ideas leads to the highest absolute – that of Good. In addition, the theory claims that states of being are contingent upon the mingling of various Forms of existence, that knowledge is objective and thus clearly more real, and that only the processes of nature were valid entities. However, Aristotle attacks this theory on the grounds that Plato’s arguments are inconclusive either his assertions are not al all cogent. Aristotle says, or his arguments lead to contradictory conclusions. For example, Aristotle claims that Plato’s arguments lead one to conclude that entities (such as anything man-made) and negations of concrete ideas could exist – such as “non-good” in opposition to good. This contradicts Plato’s own belief that only natural objects could serve as standards of knowledge. Also, Aristotle refutes Plato’s belief that Ideas are perfect entities unto themselves, independent of subjective human experience. Ideas, Aristotle claims, are not abstractions on a proverbial pedestal but mere duplicates of things witnessed in ordinary daily life. The Ideas of things, he says, are not inherent to the objects in particular but created separately and placed apart from the objects themselves. Thus, Aristotle says, Plato’s idea that Ideas are perfect entities, intangible to subjective human experience, is meaningless, for all standards are based somewhere in ordinary human activity and perception. Thirdly, Aristotle assails Plato’s efforts to find something common to several similar objects at once, a perfect exemplar of the quality those things share. Beauty is a perfect example; Plato considered Beauty both a notion and an ideal, isolated by abstractions and fixed permanently while its representatives fade away. Aristotle claims that abstractions like Beauty cannot be cast as absolutes, independent of temporal human experience; the Idea of Beauty changes with time and individual perceptions and cannot (as Plato felt) exist forever as a concrete standard. Plato and Aristotle reach some agreement, though, on the topic of reality. Plato believes that all reality was derived from his Ideas (which themselves dealt with concrete hierarchy of rational ideas. St. Anselm, though, makes the most dogmatic and logically tortuous case for God’s existence, relying not upon explanations of goodness, truth, or rational order of ideas but upon an absurd argument. He claims that everyone has some sense of God, and he claims that for one to deny God’s existence is an invalid and contradictory assertion; therefore, God exists. Also, Anselm believes that those capable of understanding God cannot believe that he does not exist as if the enormity of the idea was so clear than only a fool could not perceive it. His arguments seem the weakest of the four viewpoints here, for they are riddled with dogma and assume that God is a constant using faith alone. Anselm considers faith paramount to logic or other forms of thought and asks no questions as to what powers the universe or what goodness is – he basically follows the Christian “party line” too closely to be valid. In general, St. Augustine combines Plato’s idea of a moral hierarchy with his own rational observations of truth and goodness being embodied in their highest form by God. While Plato wavers on God’s superiority, Aristotle views man as god’s pawn, and Anselm uses tortuous dogmatic logic, Augustine’s arguments seem to make the most sense from not only a Christian point of view but from a moral and rational one as well. The philosophies of Plato, Aristotle, St. Augustine, and St. Anselm on the existence of God all vary on the issue of God’s nature; though each thinker takes a different approach to why there is a God, that of St. Augustine seems the most valid because he takes a rational stance and does not dogmatically assume God’s existence. Plato’s philosophy assumes that God exists as a supremely good being whose goodness is analogous to Plato’s concrete concept or the ultimate good. However, God and goodness are not one and the same; Plato does not directly state that goodness is good, but that God is good, since he exemplifies the idea at the top of Plato’s hierarchy. In short, God does not equal goodness, but God encompasses it better than any other being. This implies not that God is perfect, but that God’s intentions and actions have good aims – goodness may emerge from other sources besides God. The main problem with Plato’s philosophy is his inconsistency; he owes the existence of his Ideas to both God and goodness, but he claims the two are not identical. God becomes subordinate to the “universals” in Plato’s ordered cosmos, and his defense of God appears rather weak. While Plato assumes God exists as the ultimately good (but not omnipotent) being, Aristotle questions God’s active role in the universe and claims that nature depends upon an immaterial Supreme Being. For example, he cites natural genesis and the perpetuity of movement as evidence of God’s immaterial existence, and he implies that God is a self-sufficient, compelling force for both nature and man. Aristotle’s concept of God seems valid as a pre-scientific explanation of the universe; however, he seems to ignore God’s embodiment of moral goodness and man’s ability to think and act freely and still be good. He believes that all goodness comes from within God and that the goodness in man is drawn toward God and nothing else. Aristotle’s ideas on God seem, from a modern point of view, effective only as explanations of the supernatural and even of the miracle of life. St. Augustine links God with rational thought and states that human knowledge of truth depends upon man’s relationship to God. His argument moves him from existence of the self to the objectivity of truth and finally to God’s reality. Augustine assumes that God is a rational being and that the rational and the good are identical. Only God could be superior to truth, he says, and therefore must be the ultimate good; therefore, truth, goodness, and God are one and the same. His argument seems fairly clear-eyed and rational, for he does not approach God’s goodness dogmatically or automatically assume God’s existence. Instead, he works toward that end by evaluation the rationality of truth and goodness, and he casts God in that role as the ultimate embodiment of both. In general, Augustine implies, God represents goodness and occupies the pinnacle of the concept like unity and goodness. He considers unity and goodness the combined center of his system of Ideas and stated that the Ideas had to be more real and concrete than any objects of ordinary experience. Aristotle, meanwhile, agreed with Plato’s notion that the immaterial (form) and the material (matter) were distinctly separate entities; however, he did not share Plato’s belief that all forms were permanent, freestanding truths; he felt that form correlated to matter. Ideas, he stated, correlated to something material and was thus changeable and often dependent upon the observer. In general, Aristotle refutes Plato on the grounds that his Theory of Ideas tries too hard to establish concrete, universal definitions for things that depend too much on the material. Though both thinkers agree on the separation of the material and immaterial (which gave both a somewhat similar view of God), they still differ sharply over the permanence of standards by which human nature and endeavor can be judged.