Subjectivism is a problem of epistemology (theory of knowledge). The word describes the fact that we can only understand the world through our own senses and our own rational deliberations, in conjunction with our own limited experience in life. Our brains are imperfect organic machines, not a mystical repository of truth. Our senses are imperfect, our point of view limited, and the reality we experience is never the total picture. Our divergent contexts result in each of us interpreting, understanding and perceiving the world differently to one another even when looking at the same stimulus. Human thought is infused with systematic thinking errors. Our knowledge of absolute reality is hampered by our limited insights and imperfect brains, and we can never truly escape from the shackles of our own minds. Our total take on reality is a mix of guesses and patchwork. These problems have been debated by the most ancient philosophers, thousands of years ago, and no practical answers have yet been forthcoming.1.
Everyone experiences a different reality and there is no way to reconcile the experiences of two different people. Our internal worlds are unverified. No knowledge is absolute. To accept this doubt behind every theory and fact is the scientific way - evidence and logic must back up theories, but theories are never irrefutably proven, they always remain not-yet-disproven. The psychologist William James wrote that many interpretations of reality are arrived at because people find them nicer or better for themselves:
“The obvious outcome of our total experience is that the world can be handled according to many systems of ideas, and is so handled by different men, and will each time give some characteristic kind of profit, for which he cares, to the handler, while at the same time some other kind of profit has to be omitted or postponed.”
The result of all this fog is subjectivism, the realisation that our realities as we experience them are completely tied up with personal experience and personal mental traits. Any attempts to learn "absolute" truths will fail, simply because our Human brains are not equipped to deal with reality in an objective way.
The same fact presented to two people will be interpreted and stored in two different ways. It's almost as if there is no "real" world... just millions of versions of the world and we just haven't got the mental power as living beings to see what is real and what is not outside of our own experience. To rely on logic and reason leads to problems where one person concludes that another's experience is false. For example a psychiatrist concludes that a patients' experience of government conspiracy is a false experience - even though it's an experience the person has been having consistently for ten years - at the end of the day it's only one persons' point of view versus another and logic is not self-affirming of the world, only self-contained. These epistemological problems undermine any effective employment of any idea of objective reality.
All of our knowledge about everything is incomplete. Every being only ever sees a tiny fraction of reality, and all our logic, emotions and heuristics are instinctive best-guesses. Any theory about reality, from routine physics theories to outlandish religions, rely on the shared experiences of mankind. Yet even if you combine the efforts of millions of people you do not guarantee that in consensus, you find actual truth. The entire Human species has been wrong on major aspects of reality - the Earth is not flat, for example. If mass belief isn't a guide to what is true, then, how can any individual ever ascertain truth, amidst his own personal limits of knowledge?
There is an arena of thought where organisations have tried to force human thought into specific forms, and has consistently failed: religion. No matter how hard clerics try, individuals automatically and instinctively come to have different beliefs: sometimes in a minor way and sometimes in a way that causes entire new religions to emerge. There are no recorded cases of religious communities all believing the same things together. The Catholic priest and psychoanalyst W. W. Meissner says "belief systems, as they come to be individually internalized, always bear the stamp of the individual's personality"3.
Robin Le Poidevin is Professor of Metaphysics at the University of Leeds. He highlights this problem on his book on time and space quoted from below. What he mentions with reference to time equally applies to measurements of distance, and eventually, to the description of all events and realities.
“Although we could perform a test that would show some kinds of timepiece to be more accurate than others, it [is] impossible to tell whether an instrument was 100 per cent accurate since all one had to judge accuracy by was other instruments, whose accuracy could always be called into question.”
"Travels in Four Dimensions: The Enigmas of Space and Time" by Robin Le Poidevin (2003)4
We see colors via "rods" and "cones" in our eyes. The rods, color-vision, come in three types receptive to red, green and blue. Our responses to colours and patterns of colours is altered by our early upbringing; people who are subject to extreme conditions (such as solitary confinement) can end up with depth sensitivity and colour perception that is radically different to other people. Also, genetic differences mean that some people can have radically different perception of colors.
A person born in the countryside develops naturally a more subtle and richer perception of countryside colours, but a person born in the city will distinguish between grays more readily, and to him countryside colors all look a bit more similar than they do to a person accustomed to them. Our life experiences and upbringing affects the clarity with which we see colours. As no two people have the same experiences, all people do view colours slightly differently for both genetic and historical reasons.
Although objective reality remains the same, the limitations of our basic senses means that all individuals literally see the world differently. Subjectivism would be a boring topic if this was the extent of our epistemological problems, however. We could simply (as we have done) construct machines and devices that can see more clearly and accurately than we can, measuring colours precisely according to wavelength. Subjectivism, however, extends not only to all our senses, but to all of our thinking, as our very thought patterns are changed from our interaction with our environment: an interaction that is dominantly driven by our imperfect senses.
The neurones and chemistry that make up our brains is fundamental to our experience of the outside world. Our neurology is formed by our biology and genes, the rest by our experiences and environment. In all areas of development, which result in us thinking in the way we do, change and variation occurs that occurs in no-one else. Everyone is unique; the neural networks that make up your brain and form your thoughts are different to those that form other peoples' thoughts.
“Despite the fact that the structures of the brain which give rise to conceptual abilities and self-consciousness arise at the level of species, there is no uniformity between individuals. [...] In consequence it can be asserted with confidence that no two individuals will experience the external world in exactly the same way. Edelman (1992) draws this point out clearly when he claims that the collection of individual and subjective experiences, feelings and sensations associated with awareness are unique to each individual. These experiences, feelings and sensations are termed qualia and they will be subtly different between individuals because the same synaptic pathways which underpin neural structures are never repeated.”
“We all suffer from systematic thinking errors6,7 which fall into three main types: (1) internal cognitive errors; (2) errors of emotion8, perception and memory; and (3) social errors that result from the way we communicate ideas and the effects of traditions and dogmas. Some of the most common errors are the misperception of random events as evidence that backs up our beliefs, the habitual overlooking of contradictory data, our expectations and current beliefs actively changing our memories and our perceptions and using assumptions to fill-in unknown information. These occur naturally and subconsciously even when we are trying to be truthful and honest. Many of these errors arise because our brains are highly efficient (rather than accurate) and we are applying evolutionarily developed cognitive rules of thumb to the complexities of life9,10. We will fly into defensive and heated arguments at the mere suggestion that our memory is faulty, and yet memory is infamously unreliable and prone to subconscious inventions. They say "few things are more dangerous to critical thinking than to take perception and memory at face value"11.
We were never meant to be the cool, rational and logical computers that we pretend to be. Unfortunately, and we find it hard to admit this to ourselves, many of our beliefs are held because they're comforting or simple12. In an overwhelming world, simplicity lets us get a grip. Human thinking errors can lead individuals, or whole communities, to come to explain types of events and experiences in fantastical ways. Before we can guard comprehensively against such cumulative errors, we need to learn the ways in which our brains can misguide us - lack of knowledge of these sources of confusion lead many astray13.
Learning to think skeptically and carefully and to recognize that our very experiences and perceptions can be coloured by societal and subconscious factors should help us to maintain impartiality. Beliefs should not be taken lightly, and evidence should be cross-checked. This especially applies to "common-sense" facts that we learn from others by word of mouth and to traditional knowledge. Above all, however, our most important tool is knowing what types of cognitive errors we, as a species, are prone to making.”
“Moralists rarely agree on what morals to follow. So many situations are unique, special and complicated, that it seems impossible to find any absolute morals that provide guides on how to behave in all circumstances. Even when we wisely adhere to the great teachings of ethical giants, we are still subject to our own personal opinions on what they meant. It is impossible to communicate the absolute. If an absolute moral ethic was ever codified, then, interpretation would have to be the main effort, and would be the cause of many disagreements about what the absolute ethic meant. It is impossible to dictate an absolute moral because we all understand things subjectively.
If there is a good God watching over us all, it seems quite clear that such a being has not given us any absolute moral guidelines nor has it given us the mechanism to appreciate absolute morals, nor absolute facts, of any kind. The nature of the absolute means that all people would have to be given the same rules15; not one set to the Hebrews and another to the Christians, and a different set to the Muslims. There are no absolute morals and if there were, Human subjectivism denies us the possibility of us perceiving them. These problems have been a keystone of philosophical thought. Aristotle taught that in moral thought "systems of rules", "exactness" and "fixedness" are unattainable and intrinsically faulty as it is more important that "it must be left in each instance to the individual agents to look to the exigencies of the particular case"16. It is this conclusion - that of the relative subjectivism of each particular case, where most people's concept of justice and ethics correctly begin.”
Solipsism is an extreme extrapolation of subjectivism. It arises as a result of an epistemological problem: everything we know is the result of internal thought. It is possible that everything we see, the entirety of what we consider "reality" is an illusion or a trick. Any one of us could be completely insane, suffering from grand delusions, where nothing that is experienced corresponds to reality. Some people involuntarily live long periods of their lives in such a state, hallucinating their lives away17. Metaphysical solipsism is the belief that "your own mental states are the only states": Only your self exists, nothing else18. All is a creation of your imagination, including other beings. Those other beings may appear to be alive but they are actually projections of your own subconscious being - their subconscious is your subconscious, and your limited view of their lives derives from your deeper mind playfully denying your conscious self full knowledge of what is really going on. The whole world plays out in your imagination. Although it is impossible to disprove solipsism, there are some strong arguments against it.”
Quantum Physics is a vastly important area of physics for philosophers, most philosophers have (or should have!) a running interest in quantum physics, and I would guess that all the greatest scientists in this field have strayed long and hard into epistemology and the metaphysics of philosophy.
Heisenburg's Uncertainty Principle is the fact in quantum physics (the study of miniscule particles) that if you observer/measure a particles precise position, you cannot know its speed, and vica versa. This phenomenon is a mathematical catch 22 - it is impossible to measure one thing without altering another. Also all observation slightly changes what is being observed. So even with the most expensive and accurate scientific equipment, measurement causes error and a lack of knowledge. At a very fundamental way, at the height of science, we know that we cannot obtain absolute knowledge.
We all experience things differently. The same event is experienced in a different way by everyone and everything that witnesses it. This is because everyone's brain is wired up slightly differently, on account of their genotype and phenotype, upbringing and expectations. Given that this is all incontrovertible, how is it then we can share our experiences, and live in a common world, rather than individual solipsistic universes?
The answer is that we arrive at a reality by consensus. We all call the sun "yellow", no matter what actual shade we see the sun as - and despite the fact that we only see a fraction of wavelengths that the sun emits because our eyes themselves can only see certain wavelengths. We all put "happiness" and "sadness" on the same scale, even though we all experience them to different extents, and we all describe the world in standard ways using our languages, basing our communications on shared understandings of what the words mean. This is because although we experience things different, we can still try to communicate ideas to each other.
We point at things and give them names. Each person who looks at a thing will see it from different perspectives, have that thing invoke different memories and emotions, and think about that thing with different neurones and thought patterns. We might as well say that one person sees Object A and another sees Object B and there is simply no way for them to agree. But us Humans are pragmatic creatures who simply like to get on with life without letting philosophical problems get in our way. So, when two people perceive this object differently, they will in general both call it by the same name, and discuss it using shared words despite differences in perception. This way, dialogues can continue. Pragmatically, the dialogue is meaningful. Subjectively, it is only semi-meaningful. For those philosophers who are passionate about objective reality, the dialogue is pretty meaningless until both people agree on what exactly they are talking about, which can never happen.
Thankfully, although everyone lives in their own perceptual and conceptual worlds, we simply call things by their names, discuss concepts by their labels, and blunder blindly on hoping that practical outcomes are more important than the epistemological problems of subjectivism. In the material world, this is perfectly adequate. It is less satisfactory when we consider ethics and religion.