Perception is theory-laden

Compare the the hot air balloon below when it is in the shade and when it is in the light. You can tell that they are the same colours in both instances even though they actually appear to be different. In the shade the white appears pink, and what is sky blue in the light is royal blue in the shade, etc.

Why do you not assume you are looking at two different hot air balloons very close to one another? Weirdly, you know they're the same thing precisely because you know they're the same colours (despite the fact that they don't actually appear to be the same colours at all).

This is because of an inbuilt process called 'colour constancy' that allows us to identify something as the same colour in a variety of different lighting conditions.

But even though it comes from certain things that are already inside our brain, it is still just one theory that guides our perception. What is most fascinating is that we need not perceive colour in this way! Say if you are a painter and you need to perceive colours as they actually do appear to be, so that you can reproduce them, one does this by changing the theory used to perceive colours. Allow me to give an example.

Below is an optical illusion that works by exploiting colour constancy.

These grey squares are actually the same, however our eyes are not looking to compare the colours themselves. What our eyes do is look for clues to what lighting conditions the colours are under, and this is how they will decide what the colours are.

I'll show you what your eyes actually look at to work out the colour, and then I'll show you how to ignore what you normally see, by using the theory of colour perception painters use to paint.

On the lower square, our eyes see the light grey shading on the top and decide that the lower square must be mostly in shadow. Your brain therefore tells you that it's really a lighter grey but looks dark because the light isn't hitting it. So you actually see it as lighter.

On the other hand, the top square appears to be tilted upwards, and so your brain assumes its in full light. Plus your eyes read the dark grey around the edges as shading, which is more verification that the top square is otherwise in full light. Your brain then tells you that the top square is actually darker than the other, but appears quite light because it has a lot of light hitting it.

Because you're brain sees them as being under different light conditions, it tells you to see them as two different shades of grey, a much darker and a much lighter.

The illusion is of course broken if you cover up the light grey shading in the middle that is the main reason your eyes think the square are under different lighting conditions.



But this isn't the only way one can change their perception of the squares. A painter will be used to understanding how to isolate colours ignoring the lighting conditions. You can try this, too. If you ignore the light and dark shading and just compare the main colour of both squares, after a moment you should be able to see they are the same colour without even having to cover the middle up.

Basically, depending on which theory you use to perceive the above, actually changes what you perceive.

The first person a philosophy student should criticise is themselves

"I fear that a time and place where readers habitually try to refute their own interpretations and expectations of what they are reading are only in writers dreams." - Karl Popper

Intro to Critical Rationalism

There are many theories of epistemology that hold the truth to be objective, but Critical Rationalism is very different from the others.

Although it is epistemologically optimistic, in that it asserts that the truth exists and is accessible to us, it is also ultimiately sceptical, in that it asserts that we can't know the truth.

These days its fashionable to pose as falliblist. So perhaps the above does not sound so shocking. Many epistemologically optimistic positions tag on the disclaimer that the truth is never certain. But there is not much behind most of these disclaimers. Claims that the truth is never certain usually boil down to appeals to likelihood. That is to say, the kind of statements that go 'X isn't certainly true, but it is likely true.'

However, the claim the 'you believe X is true' and the claim that 'you believe Y is likely true' are not of a fundamentally different kind. Both appeal to certainty, (in one case the certainty of your belief that X is true, and in the other your certainty of the belief that Y is likely true). In summary: appeals to a theory being likely true do not take fallibility seriously.

In fact, critical rationalism is shocking because it is the only optimistic epistemology that takes seriously the arguments of scepticism. It is not just adding fallibility on as a disclaimer that has no real bearing. Critical Rationalism never purport to even know if a given theory might be true. 

Here's how it works:

Critical Rationalism puts forward the idea that knowledge improvement can occur by exposing our theories to rigorous criticism in the hope of eliminating the false theories. Karl Popper, the originator of CR, argued that there was an asymmetry between what he called 'positive reasons' and 'negative reasons'. (negative reasons being reasons against a theories, such as internal contradictions, external contradiction, falsification via empirical testing (for scientific theories), claims against its explanatory power and so on.).

This asymmetry leaves positive reasons relatively worthless--positive reasons can never really go towards verifying a theory. On the other hand, critical reasons are relatively accessible to us and can go towards falsifying a theory.

So thought we can't know if a given theory is true, we can work out if it's better than a rival theory if we show that it survives falsifation while the other theory has not.

You could look at it as the idea that we can never get close to the truth, at least we can't know that we are, but we can get further for from error, and in so doing, we can improve the state of our knowledge 

Underestimation of Values

There's a myth that in our last moments we reveal who we really are. That there's a 'way we are' hidden beneath our chosen, explicit values that is more telling of our true nature. For instance if one was to torture a man, believed to have a lot of courage in his daily life, one might discover he was a coward when he was found begging for his life.

There's another myth that in life or death situations our survival instincts kick in and overpower whatever values we have. For instance if one was on an abandoned island with a loved one, perhaps that love wouldn't count for much when that person got really hungry.

Both myths undermine the role of our explicit, chosen values. 

The first myth first. The idea that we reveal our true self in a life or death situation is nonsense. In life or death situations, if we act unpredictably, it's because we're panicked. People who are that panicked make rushed decisions. These decisions come out almost random, in that they easily could have gone in a different direction. Indeed people often find somewhat inconsistent behaviour in moments of pure panic.

For the second myth, similarly the idea of 'survival instincts' turns out to be somewhat misleading.

It's a device particularly used in fiction to 'raise the stakes'. There's nothing scarier than the idea of being in a dangerous situation, than being in a dangerous situation with many other people, many of whom will do what they can to survive. When watching the Titanic, for instance, it is horrific to think of that many people all fighting for so few seats on the life boats. Who among us does not imagine being in that situation and fighting for our lives? But we shouldn't underestimate the possibility that we chose that survival value, rather than it being part of some inner animal that will take over our human consciousness if things get tough enough.

A good way of illustrating this point is by looking at what *really* happened on the Titanic. On the real Titanic on ratio, more Americans survived than British people. Why? Because the British people queued for the lifeboats, and the Americans pushed in. I know, it'd almost be funny if it wasn't such a tragic event. But the bottom line is that, even in such dire circumstances, their cultural values defined them.

In life or death situations we do not escape who we are in terms of the values we have chosen for ourselves. If we do, it is only because we are too panicked to think clearly and act in an almost random way.

There is no truer self than the values we choose to live by day-by-day.

Kant Quote on Enlightenment

"Enlightenment is man's emergence from his self-incurred immaturity. Immaturity is the inability to use one's own understanding without the guidance of another." - Kant