For he, who, from being an infant or a child, becomes a corpse, is called unhappy; whereas it is set down to happiness, if we have been able to live through the whole period of life with a sound mind in a sound body. And, in reality, he, who, as in the case of an infant or a child, has a body capable of very few activities, and depending, for the most part, on external causes, has a mind which, considered in itself alone, is scarcely conscious of itself, or of God, or of things; whereas, he, who has a body capable of very many activities, has a mind which, considered in itself alone, is highly conscious of itself, of God, and of things. In this life, therefore, we primarily endeavour to bring it about, that the body of a child, in so far as its nature allows and conduces thereto, may be changed into something else capable of very many activities, and referable to a mind which is highly conscious of itself, of God, and of things; and we desire so to change it, that what is referred to its imagination and memory may become insignificant, in comparison with its intellect, as I have already said in the note to the last Proposition. Prop. XL. In proportion as each thing possesses more of perfection, so is it more active, and less passive; and, vice versa, in proportion as it is more active, so is it more perfect. Proof.- In proportion as each thing is more perfect, it possesses more of reality (II:Def.vi.), and, consequently (III:iii.and Note), it is to that extent more active and less passive. This demonstration may be reversed, and thus prove that, in proportion as a thing is more active, so is it more perfect. Q.E.D. Corollary.- Hence it follows that the part of the mind which endures, be it great or small, is more perfect than the rest. For the eternal part of the mind (V:xiii. and V:xxix.) the understanding, through which alone we are said to act (III:iii.); the part which we have shown to perish is the imagination (V:xxi.), through which only we are said to be passive (III:iii. and general Def. of the Emotions); therefore, the former, be it great or small, is more perfect than the latter. Q.E.D. Note.- Such are the doctrines which I had purposed to set forth concerning the mind, in so far as it is regarded without relation to the body; whence, as also from I:xxi. and other places, it is plain that our mind, in so far as it understands, is an eternal mode of thinking, which is determined by another eternal mode of thinking, and this other by a third, and so on to infinity; so that all taken together at once constitute the eternal and infinite intellect of God. Prop. XLI. Even if we did not know that our mind is eternal, we should still consider as of primary importance piety and religion, and generally all things which, in Part IV., we showed to be attributable to courage and high-mindedness.