A  Modern  Thinker Philosophy  of
Psychology  Science  Metaphysics

Home Emotion and Abreaction List of  Articles Glossary
< previous Article 1 of Section 4.  Mind next >

Subjective Idealism

The links in the table on the left take you to sub-headings on this page.


Two Views of Reality

When I open my eyes in the morning a world of objects greets me. But do these objects really exist ?  Realism (or philosophical materialism) is the view that these external objects do in fact exist and are composed of a substance called matter ; these objects are independent of me, and will continue to exist even if tomorrow I cease to exist.

The opposing philosophical theory to realism is called philosophical Idealism, or even just  Idealism.

Sub - Headings
Real or Unreal
Two Omissions

( I use a capital ‘I’ in Idealism to distinguish it from ordinary idealism ; in the latter I am motivated by ambition and ideals. This style is necessary since I use both terms in my writings).

Philosophical Idealism is the view that matter does not exist in its own right, that in fact it is a product of mind. So all objects are mental creations. In this view, since the whole world is the sum of all objects, then even the world is a mental construct.

All views of reality are variations of these two basic views. There is no conclusive way to decide between them. There is no experiment that can be performed to decide whether reality is formed by realism or by Idealism. Ultimately the test is in the explanatory power of either view: whichever one best explains the empirical phenomena of reality is the one more likely to be true. The individual has to think his way to the truth.

However, this is an optimistic belief. Some phenomena are best described using the theory of realism, whilst other phenomena are best described by Idealism. For example, in attempting to understand the basis of phenomena that are usually labelled as miracles, magic, spontaneous healing, or shamanism, the best theory to adopt is that of  Idealism. So in practice, a thinker will decide what phenomena are most important to him, and then endorse the theory that best interprets them.

Philosophical Idealism comes in two forms : subjective Idealism and objective Idealism. In this article I give an overview of subjective Idealism, the view that the individual’s mind is paramount.

Top of Page

When I see a tree, what I really observe is the idea of that tree in my mind. The point at issue is whether that tree exists independently of the idea of it that is in my mind. If so, how do I know that my idea of it is a true likeness to it ; it is impossible for me to compare my idea of the tree with the tree itself – all that I can ever observe is my own idea.

My mind is composed of ideas and not objects, and so my mind cannot empirically verify the existence of any object. Even when I touch a tree, the sensation of touch just produces an idea in my mind. And when I smell its fragrance, the sensation of smell also only produces an idea in me.

The difficulty here is that none of the five senses are of any use in verifying that an external world of objects is independent of my perception of it.

Usually, for thinkers who embrace this form of  Idealism, there is confusion about the nature of the mind : will, emotion, feeling, and desire are all considered to be aspects of the mind. Whence consciousness becomes equated to the mind.

( In objective Idealism, treated in a later article, consciousness is not the same as mind).

Idealism (whether subjective or objective) has a long pedigree. It was first propounded in Buddhism over fifteen hundred years ago, in the doctrines of  Yogacara and Vijnanavada, and flourished till the twelfth century. Descartes introduced a form of it into European thought. Other European thinkers who embraced it, in different forms, were Berkeley, Hegel, Bradley, and Brunton (as well as myself).

Top of Page


George Berkeley (1685-1753) was an Irish philosopher who originated the British tradition of  Idealism. He was an anti-materialist : he denied that matter could exist on its own unsupported by a higher spiritual reality. In his view, only spiritual activity was real. His famous insight was that esse is percipi – that is, existence occurs through perception.

In Berkeley’s view, all our thoughts, passions, ideas exist within the mind. Anything that is outside of mind is unintelligible ; it is impossible that we should ever come to know it, and so we cannot even think about it. Hence anything that is outside of mind has no meaning for us.

If something is outside of mind, then we cannot receive any sensory input, any sensations, from it. This means that we cannot even perceive it. We cannot detect it in any way. Sensations are meaningless except to the mind that receives them. All the ideas that we have of objects are derived from sensation and so are set within mind.

Objects require a mind to perceive them. It is impossible for us to imagine any sensible thing or object distinct from the sensation or perception of it. Imagination is based on what we have already seen. Even mythical ideas like centaurs (which we have never seen but can imagine) are composed of a montage of other ideas (like legs, body, head) that we can perceive. The sensations of objects are inseparable from the ideas of them.

Objects exist, but they are not composed of an independent medium called matter ; their existence depends only on their being perceived by an observer. A mind relates only to other minds. Ideas relate only to other ideas. If an object did exist that was not related to mind, which means that it would have to be an unthinking thing, then how could it form a mental image in us ?  If an object is not related to mind, then it cannot affect our mind ; conversely, for an object to affect our mind it must be a mental product.

To see an object implies that the object is a mental construction, irrespective of whether that object is as tiny as an ant or as huge as a galaxy of stars.

In his book ‘Principles of Human Knowledge ’, Berkeley expressed his insight this way:

‘… For as to what is said of the absolute existence of unthinking things without any relation to their being perceived, that is to me perfectly unintelligible. Their esse is percipi; nor is it possible they should have any existence out of the minds of thinking things which perceive them.

... all the choir of heaven and furniture of the earth, in a word all those bodies which compose the mighty frame of the world, have not any subsistence without a mind ; that their being is to be perceived or known; that consequently so long as they are not actually perceived by me, or do not exist in my mind or that of any other created spirit, they must either have no existence at all, or else subsist in the mind of some eternal spirit: it being perfectly unintelligible and involving all the absurdity of abstraction to attribute to any single part of them an existence independent of a spirit. To be convinced of which, the reader need only reflect and try to separate in his own thoughts the being of a sensible thing from its being perceived.

From what has been said, it follows, there is not any other substance than spirit, or that which perceives.’

Top of Page


Berkeley delightfully dabbles in the theory of mind. But it is Paul Brunton (1898-1981) who had the depth of insight and philosophical skill that really conjures up the strangeness of it. Brunton’s style of presentation is perhaps the best and clearest in the English language. He is excellent on the difficulties that have to be faced in the search for truth.

The cause of my becoming an Idealist was the explanation of perception given by Brunton, in his book ‘The Hidden Teaching Beyond Yoga’. Perception is that which governs my life, both when I am awake and when I am in dreaming sleep ; it is only absent during the time of dreamless sleep. So for me the deciding factor in my choice between materialism and Idealism was which one best explained perception.

I review the materialistic, physiological exposition of perception.
I look at a tree in front of me. I see it because it reflects light towards me. Then a sensory impulse enters my eye and causes a reaction on my retina. An electrical impulse then travels down the optic nerve to the region of the brain that presides over perception. So far the process has been entirely physical. Now, however, a mental image of the tree appears in my mind.  How has the physical brain produced an image in my mind?  The brain and the mind are qualitatively different, so how have they managed to interact ?   The materialist explanation breaks down at this crucial point. The transition from physical brain to non-physical mind becomes an insoluble mystery.

Brunton’s understanding of perception has greater explanatory power, which I come to in a moment. First of all, ideas and images always centre on relations, and these relations are created by our minds and not by the objects. When relations are obscure and vague then the ideas and images are also obscure and vague. What we know about objects are only the relations between them, and these relations change as we change our perspective. Nothing seems unique – any one thing is related to other things.

Even the observer is related to his observations, since those observations depend upon the perspective of that observer. Everything is relative. Brunton uses the term ‘relativity’ in its traditional sense of meaning ‘relational’, that is, we can only know the relations between things, and the description of anything is just comparative.

At this point we need to clear up a couple of confusions about the mind.

One of the mis-understandings of traditional philosophy is the view that the mind is not located in space, as the brain is. This view is erroneous. The mind does extend into space. The body is surrounded by an aura, and this aura is located within the mind. A person who has developed an ability in extra-sensory perception can see that the aura, and hence the mind, extends into the space beyond the body.

Another source of confusion, as Brunton points out, arises from believing that because an object is external to the body, so then it is also external to one’s mind. If something is external to the mind then it is outside the field of perception, and hence cannot give rise to images in that mind. This means that anything which is outside the mind cannot be seen or thought of ; any attempt to think of something which seems to be external to the mind automatically brings it within that mind. So the notion of  ‘external’ is inapplicable to mind.

Top of Page

Now I return to Brunton's view of perception.
To understand perception we need to consider sensation. When I touch a book, that touch creates a sensory impression or sensation in me. However, this sensation is not a sensation of the book but the sensation of what is happening to my fingers. The sensation is just a state of mind in me, yet I erroneously ascribe it to the book. Hence I have projected a state of mind onto something which I assume is external to me. The sensation of the book is associated with the thought of the book. Likewise with perception: the visual (sensory) impression of an object is associated with the thought of it. But which comes first, the sensation or the thought ?

Brunton challenges the view that the sensation of an object comes before the idea of that object. We need to accept that the sequence of perception does not begin with sensation. The image of the object on the retina is upside down and only two-dimensional. Therefore this retinal image has to be interpreted by the mind before a realistic image of the object can appear in consciousness. The instant that the image appears in our mind is the instant when we first become aware that the object is there in front of us. Awareness does not start from the retinal image, nor from the brain’s response to it, but only when the image first arises in our mind.

Brunton brings up the example of reverie to illustrate the fact that if our awareness is switched away from the external world, then even if sensory images are formed on the retina and transmitted to the optical centre of the brain, no images subsequently arise in our mind due to them. In other words, a man cannot smell a rose until his mind intervenes, until he thinks of it first.

What is the difference between a rose and my body ?  Both are objects to my consciousness. The sensory impressions that I have from the external world are no different in kind from the sensory impressions that I have of my own body. Therefore my body is also known mentally ; it has to be treated on a par with all other objects. My awareness of my body is similar to my awareness of the world, that is, it is solely the awareness of thought.

What is the relation between the perception of an object and that object itself ?  For Berkeley the perception of an object is that object. Brunton follows this interpretation, though his theory is even more subjective. The difficulty is that we can never get directly in contact with any object. We can only deal with its image. So how can we verify that it exists separately from our thought of it ?

Brunton argues that we cannot separate any object from the perception of it. The object cannot be completely objective ; it needs a subjective observer. For every object that is seen there must exist an observer ; if there is no observer then the existence of an object cannot be known. Nothing can be known unless there is a knower. The thought of the object is inseparable from the object itself. Brunton then contends that the perception of the object is that object. The thought arises in the mind, so too therefore must the object.

The perception of the object is that object.
This axiom is the hallmark of subjective Idealism.

Top of Page

From these ideas we can see where the physiologist went wrong : he has explained the process of perception in the wrong order !   He needs to start the process from the mental image, which is in the mind. The eyes and brain are also in the mind. Therefore there is no problem at all about how sensory impressions create the mental image. From first to last everything is mind.

What, therefore, is the need for the five senses, since they are all within the mind?   They provide the conditions that facilitate the arising of the individual consciousness. Their limitation is that they cannot verify that an external world of objects exists independently of the observer.

Would we be better able to establish the independent existence of objects if we possessed a higher sense?  Can extra-sensory perception and psychic abilities make it easier to handle the strangeness of  Idealism?  Berkeley disposes of this hope. If we had a new sense, it could only furnish us with new sensations and new ideas ; and then we are back into the problem of the origin of these new sensations and new ideas.

Top of Page

Real or Unreal

Brunton followed the Kantian idea that space and time are attributes of mind. Brunton accepts that time is a condition of the thinking process (time allows for sequential change of ideas) and space is a condition of the perceptual process (space is needed in which to place objects). He then moves from the view that space and time are ‘relative’ (that is, relational) to the mind of the observer, to the view that space and time are contained within the observer. In this latter view, what is happening when we see an external object, such as a rose?  He deduces that since the rose exists in space, and space exists within the mind, then the rose can exist nowhere except in the mind itself.

This understanding leads Brunton to the question of whether each object is unreal. To answer this we need to separate two concepts that are often conflated together. In considering illusions we can postulate that they exist but that they are not real. Illusions appear to be real, but our reason can tell us that they are not. However, they certainly exist. We have to reject their reality.

Berkeley’s view that existence depends upon perception now needs to be coupled with Brunton’s view that perception is no proof of reality.

The philosopher accepts the existence of objective things ; therefore his task is to determine whether they are real or unreal. The world is a relative world. The quest for truth has to transcend relativity. The quest for truth finally leads us to the quest of what is real.

Top of Page

Two Omissions

Brunton’s explanation of perception was the key factor that converted me to philosophical Idealism. Since I have a scientific training I am aware of the limitations of the scientific outlook, and so did not need to be persuaded that the materialistic explanation was hopeless. Brunton explained perception in a philosophically coherent way. So I adopted it. The crux of the matter is that perception is that which the person’s life revolves around, every hour of the day and night. And materialism cannot explain perception.

Brunton’s presentation of the theory of mind became the raw material out of which I evolved my own understanding of it. There are two serious omissions from his presentation : not being a psychologist he did not consider the problems of determinism and subconscious motivation, and neither did he bring personal relationships into his theorising. It was these issues that caused me to reconstruct his concept of  Idealism.

He used a model which treated desire, will, emotion, and feeling as aspects of mind (as Descartes did). I do not accept this presentation. In the model that I subsequently adopted, these were either separate from, or related to, mind. I cannot see how mind can act on itself, whereas it seems very obvious to me that will and feeling can act on it. Therefore my theory is different from Brunton’s one.

In terms of labels, Brunton is a subjective Idealist whereas I am an objective Idealist.

It took me several years to understand Brunton’s views. My slowness in understanding arose because I cannot handle new concepts until I become familiar with them.

There is no way to speed up the understanding of strangeness !

Top of Page



Berkeley, George. Principles of Human Knowledge. Included in Philosophical Works, Dent (Everyman's Library), 1985. pages 78-79

Brunton, Paul. The Hidden Teaching Beyond Yoga. Rider, 1944 ?

Home List of  Articles Links Top of  Page

The articles in this section are :

Subjective Idealism

Criticisms of Subjective Idealism

Will and Representation

Objective Idealism

Copyright @2003  Ian Heath
All Rights Reserved

The copyright is mine and the articles are free to use. They can be reproduced anywhere, so long as the source is acknowledged.

Ian Heath
London, UK


e-mail address:

If you want to contact me, use the address above but replace the <at> by @

It may be a few days before I can respond to correspondence.