I. Definition

In popular usage, an idealist is someone who believes in high ideals and strives to make them real, even though they may be impossible. It’s often contrasted with pragmatist or realist, i.e. someone whose goals are less ambitious but more achievable.

This sense of “idealism” is very different from the way the word is used in philosophy. In philosophy, idealism is about the basic structure of reality: idealists hold that the most basic “unit” of reality is not material, but conceptual.

But what does that actually mean? What are people talking about when they say that reality is conceptual rather than material? Answers vary widely.


II. Types of Idealism

Idealism doesn’t have well-defined sub-schools, but here are some labels for the purpose of this article:

a. Subjective Idealism

For some idealists, it means that nothing is truly real other than consciousness and its contents. That is, when you look out on the world what you are really seeing is a world created by the mind. Perception, in other words, is reality. That doesn’t mean that you’re stuck in your own mind, though, since we’re lucky enough to have other minds that we can communicate with. Thus, the truth may lie somewhere in between your mind and mine (but still not in any external physical world). We can call this intersubjective idealism.

b. Divine Idealism

Alternatively, the world may be seen as manifestations of some other mind, such as the mind of one God. (However, remember that all of physical reality would be contained in the mind of God on this view — so God would have to be a consciousness outside of the physical multiverse!)

c. Ontological Idealism

Others don’t take it quite as far: they argue that the material world exists, but that at its most basic level it’s made out of ideas. For example, some physicists believe that the universe, at its most basic level, is made of numbers. So scientific formulas don’t just describe physical reality; they are the physical reality. E=MC2, for example, would be seen as a fundamental aspect of reality which Einstein discovered, rather than a description that he invented.

d. Epistemological Idealism

Maybe it doesn’t actually matter whether there’s a physical world beyond the mind. After all, the mind is our only tool for understanding that world, and therefore all of our perceptions and understandings will be constrained by the structure of the mind. When we try to understand that structure, we may not be exploring the most basic truths of the universe (as ontological idealists would claim); rather, we’re just trying to understand the human mechanisms and tools that make all understanding possible.

Idealism also has a place in the analysis of history. Historical idealists hold that human history can be explained as the a process of ideas changing and evolving, and that ideas shape human beings rather than the other way around. This process, according to historical idealism, will eventually reach a stage of “complete expression,” when no more unfolding will be possible. At this point, history will end as there will be no more changes to human society (and, by extension, human consciousness). Very few historians accept this view today, since it seems that chaotic historical change will go on forever; but in the past, many historians believed that we would someday reach the end of history.


III. Idealism vs. Materialism

The opposite of idealism is materialism, or the view that reality is material instead of conceptual. For materialists, the physical world is the only true reality. Our thoughts and perceptions are part of the material world just like other objects. Consciousness is a physical process in which one chunk of matter (your brain) interacts with another (the book, screen, or sky that you’re looking at).

Idealism and materialism are both impossible to prove or disprove, of course — they’re unfalsifiable statements, which means there’s no neutral test that could weigh them against each other. The test, ultimately, has to be one of intuition, or “gut reaction.” Many people find that materialism makes more sense because, after all, everyone has the experience of interacting with an outside world and believing that’s really “out there.” On the other hand, it’s impossible for us to step “outside” our own minds, so how can we be so sure that there really is an “out there” at all?


IV. Famous Quotes About Idealism

Quote 1

When I enter most intimately into what I call myself I always stumble on some particular perception or other….and never can observe anything but the perception. (David Hume)

Scottish philosopher David Hume famously showed that we can’t prove that there is a stable self-identity over time. That is, how can you prove that your present self is the same as the self in your baby pictures? There is no way to prove scientifically that anyone has a stable “Self” that persists over time, and yet it’s one of our strongest intuitions — of course I’m me! There are many ways to answer, including one based on modern genetics (which Hume could not have imagined), but another is to think of personal identity in terms of ontological idealism. Rather than being a physical object, your selfhood is an idea — and, in accordance with ontological idealism, that’s exactly what makes it real!

Quote 2

The universe seems to me to be nearer to a great thought than to a great machine. It may well be, it seems to me, that each individual consciousness ought to be compared to a brain-cell in a universal mind. (James Jeans)

James Jeans was a British scientist and mathematician, and a great defender of ontological idealism. In this quote, he shows the overlap between ontological idealism and divine idealism. That is, he sees scientific reality as an expression of some fundamental ideas — but he also believes that those ideas are not just floating out there in the abstract, instead arguing that a great “universal mind” contains the ideas. Although he doesn’t use the word “God,” this could be taken as a kind of divine idealism. (Jeans himself was an agnostic, meaning he believed it was impossible to know whether or not God was real.)


V. The History and Importance of Idealism

Idealism can be traced back to Plato, who developed the doctrine of the Eternal Forms. This doctrine was kind of an early form of what we’ve been calling ontological idealism: Plato held that all the objects we see around us are instances of abstract concepts. These abstract concepts are like numbers: if you have four apples or four cats or four dollars, all of these things are instances of the same abstract quantity known as “four.” But for Plato, the same thing was true for the physical objects themselves. So your four apples are not just an instance of the abstract “four,” but also an instance of the abstract “apple.” Plato’s idea of the Forms is often confusing for modern readers (perhaps because we’re much more likely to be materialists than idealists!)

One of the most famous idealists was Descartes, who famously claimed that “I think, therefore I am.” If you examine this statement, you’ll see that it’s an extreme form of idealism. For Descartes, our existence is only demonstrated by our thought, and therefore thought is logically prior to existence! To be is to think, or to be thought. Descartes saw this as the only claim that was beyond doubt. Descartes has largely fallen out of favor among modern philosophers, but we still read him due to his immense historical significance.

Today, when philosophers talk about “idealism,” they’re usually talking about “German Idealism,” a rough tradition of thought defined by the work of Immanuel Kant. Kant developed a sophisticated form of idealism based on the distinction between phenomena (“things-as-they-appear”) and noumena (“things-in-themselves”). For Kant, the mind always drew on certain hard-wired techniques for shaping the noumena into phenomena — the mind, in other words, is like a set of tinted goggles that allow us to see the noumena but always with a certain amount of discoloration and distortion. We can never perceive them directly. For example, maybe the whole idea of “material/physical” reality is one of these mental techniques! Maybe the whole distinction between “material” and “mental” is something that our mind uses to make sense of the world, but that doesn’t really exist in the “noumenal world.” This would place us in a position beyond both materialism and idealism!


VI. Idealism in Popular Culture

Example 1

What if all of reality, as we know it, was a computer program? This is the premise of The Matrix, and at first it looks like an idealist view: after all, a computer program is just an idea, an arrangement of information, not a physical object. (Computer programs are contained in physical circuits, of course, but you can copy a program from one hard drive to another and it’s still the same program — that’s what it means to say that it’s an idea.) However, in The Matrix we discover that there is an external, physical world beyond the computer program. This is more materialist than idealist. To understand ontological idealism, imagine instead that we live in a computer program, but that computer program isn’t actually installed on a hard drive anywhere — it’s just an abstract program. (Or, if you prefer divine idealism, think of God as the hard drive.)

Example 2

But you know, I’ve learned something today. You see, the basis of all reasoning is the mind’s awareness of itself. What we think, the external objects we perceive, are all like actors that come on and off stage. But our consciousness, the stage itself, is always present to us. (South Park)

In an episode of South Park (“The Tooth-Fairy-Tats”), Kyle becomes obsessed with figuring out whether there is any such thing as reality. He reads Descartes as well as several books on Taoism and quantum mechanics, ultimately becoming convinced that nothing is real. After suffering an existential crisis through most of the episode, he finally settles on a kind of mild subjective idealism. He doesn’t necessarily argue that there is no such thing as the outside world, but he does argue that we have no way of accessing that world other than through consciousness. Therefore, we must accept at least a certain amount of idealism as the price of being sentient.


VII. Controversies

Materialism vs. Idealism: a Difference that Makes no Difference?

E=MC2 is a description of reality. (materialism)

E=MC2 is part of reality itself. (idealism)

At the end of the day, what is the difference between these two statements? Is there any practical difference, or a difference that might cause us to behave in a different way? Some philosophers (and many non-philosophers) argue that this is an important test for any philosophical debate. If there is no practical difference, then it’s probably a moot question, one that really doesn’t need to be resolved. In that case, there would be no need for further argument between materialists and idealists – they could just agree to disagree, and get to work on problems with more practical implications.

Of course, this view goes against centuries of Western philosophical tradition. Since at least Plato, philosophers have argued about idealism and materialism. To them, it seemed important to pin down the fundamental nature of reality and understand whether it’s made up of matter or ideas.


Idealism can be traced back to…





The opposite of idealism is…





This article discusses which of the following types of idealism?





“Consciousness is the only reality. Fortunately, we can communicate with other consciousnesses, and the truth of reality is what lies in between my perceptions and yours.”

This statement is an example of…






  1. Reply


  2. Reply

    this information is significant in real life .congratulations

  3. Reply

    This is wow!

  4. Reply

    I scored 4/4 in the quiz after the discussion.. We need more quiz to be the 21st century philosophers.

  5. Reply

    Great explanations in ways that a layman can understand!

Leave a Reply

Your email address will not be published.

You may use these <abbr title="HyperText Markup Language">HTML</abbr> tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>