time and real at another—and similarity with any of His creatures. In this respect our knowledge of God is aided by the study of Natural Science. For he who is ignorant of the latter cannot understand the defect implied in emotions, the difference between potentiality and reality, the non-existence implied in all potentiality, the inferiority of a thing that exists in potentiâ to that which moves in order to cause its transition from potentiality into reality, and the inferiority of that which moves for this purpose compared with its condition when the transition has been effected. He who knows these things, but without their proofs, does not know the details which logically result from these general propositions; and therefore he cannot prove that God exists, or that the [four] things mentioned above are inadmissible in reference to God. Having premised these remarks, I shall explain in the next chapter the error of those who believe that God has essential attributes; those who have some knowledge of Logic and Natural Science will understand it. CHAPTER LVI Similarity is based on a certain relation between two things; if between two things no relation can be found, there can be no similarity between them, and there is no relation between two things that have no similarity to each other; e.g., we do not say this heat is similar to that colour, or this voice is similar to that sweetness. This is self-evident. Since the existence of a relation between God and man, or between Him and other beings has been denied, similarity must likewise be denied. You must know that two things of the same kind—i.e., whose essential properties are the same, and which are distinguished from each other by greatness and smallness, strength and weakness, etc.—are necessarily similar, though different in this one way; e.g., a grain of mustard and the sphere of the fixed stars are similar as regards the three dimensions, although the one is exceedingly great, the other exceedingly small, the property of having [three] dimensions is the same in both; or the heat of wax melted by the sun and the heat of the element of fire, are similar as regards heat; although the heat is exceedingly great in the one case, and exceedingly small in the other, the existence of that quality (heat) is the same in both. Thus those who believe in the presence of essential attributes in God, viz., Existence, Life, Power, Wisdom, and Will, should know that these attributes, when applied to God, have not the same meaning as when applied to us, and that the difference does not only consist in magnitude, or in the degree of perfection, stability, and durability. It cannot be said, as they practically believe, that His existence is only more stable, His life more permanent, His power greater, His wisdom more perfect, and His will more general than ours, and that the same definition applies to both. This is in no way admissible, for the