“I believe it has required a long series of accepted observations for us to have arrived at this idea, now so natural in appearance, that the modifications produced within our nervous system are the only states of which we can have a direct consciousness; and as experimental demonstration is always limited, there can be no absolute certainty that things never happen otherwise, that we never go outside ourselves, and that neither our consciousness nor our nervous influx can exteriorise itself, shoot beyond our material organs, and travel afar in pursuit of objects in order to know or to modify them.”

“When we attempt to understand the inmost nature of the outer world, we stand before it as before absolute darkness. There probably exists in nature, outside of ourselves, neither colour, odour, force, resistance, space, nor anything that we know as sensation. Light is produced by the excitement of the optic nerve, and it shines only in our brain; as to the excitement itself, there is nothing to prove that it is luminous; outside of us is profound darkness, or even worse, since darkness is the correlation of light. In the same way, all the sonorous excitements which assail us, the creakings of machines, the sounds of nature, the words and cries of our fellows are produced by excitements of our acoustic nerve; it is in our brain that noise is produced, outside there reigns a dead silence. The same may be said of all our other senses.

...In short, our nervous system, which enables us to communicate with objects, prevents us, on the other hand, from knowing their nature. It is an organ of relation with the outer world; it is also, for us, a cause of isolation. We never go outside ourselves. We are walled in. And all we can say of matter and of the outer world is, that it is revealed to us solely by the sensations it affords us, that it is the unknown cause of our sensations, the inaccessible excitant of our organs of the senses, and that the ideas we are able to form as to the nature and the properties of that excitant, are necessarily derived from our sensations, and are subjective to the same degree as those sensations themselves.”

“When we put our central nervous system outside us we returned to the primal nomadic state.”

“Whatever plane our consciousness may be acting in, both we and the things belonging to that plane are, for the time being, our only realities. As we rise in the scale of development we perceive that during the stages through which we have passed we mistook shadows for realities, and the upward progress of the Ego is a series of progressive awakenings, each advance bringing with it the idea that now, at last, we have reached "reality"; but only when we shall have reached the absolute Consciousness, and blended our own with it, shall we be free from the delusions produced by Maya [illusion].”

“I believe that we are consciousness, consciousness is energy, and energy can never be destroyed. It can be transformed, but it can never be destroyed.”

“By induction we gain no certain knowledge; but by observation, and the inverse use of deductive reasoning, we estimate the probability that an event which has occurred was preceded by conditions of specified character, or that such conditions will be followed by the event. …I have no objection to use the words cause and causation, provided they are never allowed to lead us to imagine that our knowledge of nature can attain to certainty. …We can never recur too often to the truth that our knowledge of the laws and future events of the external world are only probable.”

“As we have already glimpsed and will continue to discover, we are able to expand our awareness beyond the perceived limitations of our own person and access the dimensions of a transpersonal consciousness. As we open ourselves to the realization of the in-formed universe, this shift in our collective awareness heralds a resolution of the schisms that have divided us for so long—both among and within us”

“The most difficult thing to accept is that we are usually the source of our suffering. For example, if we believe that nothing works out for us, we never pour ourselves into our goals and so they never come to fruition. If we have decided that people always leave, we never fully commit to them and so the relationship we have with them never becomes secure.”

“ Of all forms of symbolism, language is the most highly developed, most subtle, and most complicated. It has been pointed out that human beings, by agreement, can make anything stand for anything. Now, human beings have agreed, in the course of centuries of mutual dependency, to let the various noises that they can produce […] stand for specified happenings in their nervous systems. We call that system of agreements language. For example, we who speak English have been so trained that, when our nervous systems register the presence of a certain kind of animal, we may make the following noise: "That's a cat." Anyone hearing us expects to find that, by looking in the same direction, he will experience a similar event in his nervous system -- one that will lead him to make an almost identical noise. Again, we have been so trained that when we are conscious of wanting food, we make the noise "I'm hungry."”

“We can only know in the nervous system what we have known in behavior first.”