In truth, to know oneself seems to be the hardest of all things. Not only our eye, which observes external objects, does not use the sense of sight upon itself, but even our mind, which contemplates intently another's sin, is slow in the recognition of its own defects.
There's one uneasy borderline between what is external and what is internal, and this borderline is defined exactly by the sense organs and the skin and the introduction of external things within my own body. Consciousness is altered by physical events and physical objects, which impinge upon my sense organs, or which I introduce into my body. Now the name traditionally given to external objects or processes which change you internally is sacrament. Sacraments are the visible and tangible techniques for bringing you close to your own divinity.
There is a very remarkable inclination in human nature to bestow on external objects the same emotions which it observes in itself, and to find every where those ideas which are most present to it.
As you are aware, no perceptions obtained by the senses are merely sensations impressed on our nervous systems. A peculiar intellectual activity is required to pass from a nervous sensation to the conception of an external object, which the sensation has aroused. The sensations of our nerves of sense are mere symbols indicating certain external objects, and it is usually only after considerable practice that we acquire the power of drawing correct conclusions from our sensations respecting the corresponding objects.
We see things in this material world, wherein our bodies dwell, only because our mind through its attention lives in another world, only because it contemplates the beauties of the archetypal and intelligible world which Reason contains.
These two, I say, viz. external material things, as the objects of SENSATION, and the operations of our own minds within, as the objects of REFLECTION, are to me the only originals from whence all our ideas take their beginnings.
All men naturally desire knowledge. An indication of this is our esteem for the senses; for apart from their use we esteem them for their own sake, and most of all the sense of sight. Not only with a view to action, but even when no action is contemplated, we prefer sight, generally speaking, to all the other senses. The reason of this is that of all the senses sight best helps us to know things, and reveals many distinctions.
In this external world, which is full of finite things, it is impossible to see and find the Infinite. The Infinite must be sought in that alone which is infinite, and the only thing infinite about us is that which is within us, our own soul. Neither the body, nor the mind, nor even our thoughts, nor the world we see around us, is infinite.
Our initial sensory data are always "first derivatives," statements about differences which exist among external objects or statements about changes which occur either in them or in our relationship to them. Objects and circumstances which remain absolutely constant relative to the observer, unchanged either by his own movement or by external events, are in general difficult and perhaps always impossible to perceive. What we perceive easily is difference and change and difference is a relationship.
The eye of the mind, like that of the body, can only extend its view to new objects, by losing sight of those which are now before it.
Does the open wound in another's breast soften the pain of the gaping wound in our own? Or does the blood which is welling from another man's side staunch that which is pouring from our own? Does the general anguish of our fellow creatures lessen our own private and particular anguish? No, no, each suffers on his own account, each struggles with his own grief, each sheds his own tears.
According to the technical language of old writers, a thing and its qualities are described as subject and attributes; and thus a man's faculties and acts are attributes of which he is the subject. The mind is the subject in which ideas inhere. Moreover, the man's faculties and acts are employed upon external objects; and from objects all his sensations arise. Hence the part of a man's knowledge which belongs to his own mind, is subjective: that which flows in upon him from the world external to him, is objective.
As, in Sense, that which is really within us, is (as I have said before) only Motion, caused by the action of external objects, but in appearance; to the Sight, Light and Color; to the Ear, Sound; to the Nostril, Odor, &c.
The eye observes only what the mind, the heart, and the imagination are gifted to see; and sight must be reinforced by insight before souls can be discerned as well as manners, ideas as well as objects, realities and relations as well as appearances and accidental connections.
The dew seemed to sparkle more brightly on the green leaves the air to rustle among them with a sweeter music and the sky itself to look more blue and bright. Such is the influence which the condition of our own thoughts, exercise, even over the appearance of external objects.
Sometimes differences arise partly from incomplete information. We are finite. And we should admit that there are cases of uncertainty. But often the differences become exacerbated because of sinful inclinations underneath the surface, which incline us to prefer our own ideas and not to submit to what is less comfortable. We must be cautious about accusing anyone else of sin. We don't know people's hearts. But we must also avoid being naïve about the subtlety of sin and the corrupting effects of sin on the mind - our own minds, not only the mind of the other fellow.
We exist only by virtue of what we possess, we possess only what is really present to us, and many of our memories, our moods, our ideas sail away on a voyage of their own until they are lost to sight! Then we can no longer take them into account in the total which is our personality. But they know of secret paths by which to return to us.