1. The individuals of a species arrive at the end and perfection of that species for the most part; and natural developments have place always or for the most part, though they fail in a minority of instances through something coming in to mar them. But happiness is the end and perfection of the human species, since all men naturally desire it. Happiness then is a common good, possible to accrue to all men, except in cases where an obstacle arises to deprive some of it. But few they are who arrive at this knowledge of God by way of demonstration, on account of the difficulties mentioned above (B. I, Chap. IV). Such scientific knowledge then is not the essence of human happiness.
3. Happiness excludes all misery. But deception and error is a great part of misery. Now in the knowledge of God by demonstration manifold error may be mingled, as is clear in the case of many who have found out some truths about God in that way, and further following their own ideas, in the failure of demonstration, have fallen into many sorts of error. And if any have found truth in the things of God so perfectly by the way of demonstration as that no error has entered their minds, such men certainly have been very few: a rarity of attainment which does not befit happiness, happiness being the common end of all.*
4. Happiness consists in perfect activity. Now for the perfection of the activity of knowledge certainty is required: but the aforesaid knowledge has much of uncertainty.
3.38 : That Human Happiness does not consist in such Knowledge of God as is common to the Majority of Mankind
3.40 : That Happiness does not consist in the Knowledge of God by Faith