George Berkeley

PHIL. What you call the empty forms and outside of things seem to me the very things themselves. Nor are they empty or incomplete, otherwise than upon your supposition--that Matter is an essential part of all corporeal things. We both, therefore, agree in this, that we perceive only sensible forms: but herein we differ--you will have them to be empty appearances, I, real beings. In short, you do not trust your senses, I do. HYL. You say you believe your senses; and seem to applaud yourself that in this you agree with the vulgar. According to you, therefore, the true nature of a thing is discovered by the senses. If so, whence comes that disagreement? Why is not the same figure, and other sensible qualities, perceived all manner of ways? and why should we use a microscope the better to discover the true nature of a body, if it were discoverable to the naked eye? PHIL. Strictly speaking, Hylas, we do not see the same object that we feel; neither is the same object perceived by the microscope which was by the naked eye. But, in case every variation was thought sufficient to constitute a new kind of individual, the endless number of confusion of names would render language impracticable. Therefore, to avoid this, as well as other inconveniences which are obvious upon a little thought, men combine together several ideas, apprehended by divers senses, or by the same sense at different times, or in different circumstances, but observed, however, to have some connexion in nature, either with respect to co-existence or succession; all which they refer to one name, and consider as one thing. Hence it follows that when I examine, by my other senses, a thing I have seen, it is not in order to understand better the same object which I had perceived by sight, the object of one sense not being perceived by the other senses. And, when I look through a microscope, it is not that I may perceive more clearly what I perceived already with my bare eyes; the object perceived by the glass being quite different from the former. But, in both cases, my aim is only to know what ideas are connected together; and the more a man knows of the connexion of ideas, the more he is said to know of the nature of things. What, therefore, if our ideas are variable; what if our senses are not in all circumstances affected with the same appearances. It will not thence follow they are not to be trusted; or that they are inconsistent either with themselves or anything else: except it be with your preconceived notion of (I know not what) one single, unchanged, unperceivable, real Nature, marked by each name. Which prejudice seems to have taken its rise from not rightly understanding the common language of men, speaking of several distinct ideas as united into one thing by the mind. And, indeed, there is cause to suspect several erroneous conceits of the philosophers are owing to the same original: while they began to build their schemes not so much on notions as on words, which were framed by the vulgar, merely for conveniency and dispatch in the common actions of life, without any regard to speculation. HYL. Methinks I apprehend your meaning. PHIL. It is your opinion the ideas we perceive by our senses are not real things, but images or copies of them. Our knowledge, therefore, is no farther real than as our ideas are the true REPRESENTATIONS OF THOSE ORIGINALS. But, as these supposed originals are in themselves unknown, it is impossible to know how far our ideas resemble them; or whether they resemble them at all. We cannot, therefore, be sure we have any real knowledge. Farther, as our ideas are perpetually varied, without any change in the supposed real things, it necessarily follows they cannot all be true copies of them: or, if some are and others are not, it is impossible to distinguish the former from the latter. And this plunges us yet deeper in uncertainty. Again, when we consider the point, we cannot conceive how any idea, or anything like an idea, should have an absolute existence out of a mind: nor consequently, according to you, how there should be any real thing in nature. The result of all which is that we are thrown into the most hopeless and abandoned scepticism. Now, give me leave to ask you, First, Whether your referring ideas to certain absolutely existing unperceived substances, as their originals, be not the source of all this scepticism? Secondly, whether you are informed, either by sense or reason, of the existence of those unknown originals? And, in case you are not, whether it be not absurd to suppose them? Thirdly, Whether, upon inquiry, you find there is anything distinctly conceived or meant by the ABSOLUTE OR EXTERNAL EXISTENCE OF UNPERCEIVING SUBSTANCES? Lastly, Whether, the premises considered, it be not the wisest way to follow nature, trust your senses, and, laying aside all anxious thought about unknown natures or substances, admit with the vulgar those for real things which are perceived by the senses? HYL. For the present, I have no inclination to the answering part. I would much rather see how you can get over what follows. Pray are not the objects perceived by the SENSES of one, likewise perceivable to others present? If there were a hundred more here, they would all see the garden, the trees, and flowers, as I see them. But they are not in the same manner affected with the ideas I frame in my IMAGINATION. Does not this make a difference between the former sort of objects and the latter? PHIL. I grant it does. Nor have I ever denied a difference between the objects of sense and those of imagination. But what would you infer from thence? You cannot say that sensible objects exist unperceived, because they are perceived by many. HYL. I own I can make nothing of that objection: but it hath led me into another. Is it not your opinion that by our senses we perceive only the ideas existing in our minds? PHIL. It is.