[16] In tracing our emotions and passions to their origin, it once was my opinion, that qualities and actions are the primary causes of emotions; and that these emotions are afterward expanded upon the being to which these qualities and actions belong. But I have discovered that opinion to be erroneous. An attribute is not, even in imagination, separable from the being to which it belongs; and for that reason, cannot of itself be the cause of any emotion. We have, it is true, no knowledge of any being or substance but by means of its attributes; and therefore no being can be agreeable to us otherwise than by their means. But still, when an emotion is raised, it is the being itself, as we apprehend the matter, which raises the emotion; and it raises it by means of one or other of its attributes. If it be urged, That we can in idea abstract a quality from the thing to which it belongs; it might be answered, That an abstract idea, which serves excellently the purposes of reasoning, is too faint and too much strained to produce any sort of emotion. But it is sufficient for the present purpose to answer, That the eye never abstracts. By this organ we perceive things as they really exist, and never perceive a quality as separated from the subject. Hence it must be evident, that emotions are raised, not by qualities abstractly considered, but by the substance or body so and so qualified. Thus a spreading oak raises a pleasant emotion, by means of its colour, figure, umbrage, _&c._ It is not the colour strictly speaking that produces the emotion, but the tree as coloured: it is not the figure abstractly considered that produces the emotion, but the tree considered as of a certain figure. And hence by the way it appears, that the beauty of such an object is complex, resolvable into several beauties more simple. [17] When this analysis of human nature is considered, not one article of which can with any shadow of truth be controverted, I cannot help being surprised at the blindness of some philosophers, who, by dark and confused notions, are led to deny all motives to action but what arise from self-love. Man, for ought appears, might possibly have been so framed, as to be susceptible of no passions but what have self for their object. But man thus framed, would be ill fitted for society. Much better is the matter ordered, by enduing him with passions directed entirely to the good of others, as well as with passions directed entirely to his own good. [18] See Essays upon morality and natural religion, part 1. essay 2. ch. 4.