epistemology

what is direct realism?

• the idea is that the immediate objects of perception are mind-independent objects and their properties

• objects exist independant of the mind and have properties such as size, smell, taste and colour

• these objects and their properties continue to exist and obey the laws of nature even when we are not percieving them

• we percieve them directly as they are in their MI state

• our awareness of the o and their p is unmediated

• in direct realism, we percieve the EW exacctly as it i

what is the argument from illusion against Direct Realism?

• illusions are distortions of the senses

• what we perceive is different from what exists in the external world

• if illusions are possible, then our perceptions of objects are distinct from the objects as they exist in the external world

• e.g stick in water - appears to bend despite the fact that it doesn’t

• therefore, direct realists claim that we directly perceive mind independent objects and their properties exactly as they are in the external world, they can’t explain why illusions occur

What’s the response to the argument of illusions, for direct realism - stick and barn

• science can explain how apparent ‘illusions’ are not tricks of the mind, but can be explained as genuine properties of the external world

• in the stick example, I directly perceive the process of refraction

• thus illusions are not really tricks that prevent me from directly perceiving mind independent objects

• J.L Austin - church disguised as a barn - you will come to know the object as a camouflaged church (the reality) rather than just a barn (the appearance)

• Therefore, the fact that appearance can be different from reality doesn’t stop me from having direct access to reality

What’s the problem from hallucinations - against direct realism - pink elephant

• a hallucination is a perception of an object in the absence of the object (seeing something that isn’t there, but feels no qualitatively different from a genuine perception - often multi sensory

• p1) in a hallucination, I directly perceive an object (a pink elephant)

• p2) when I hallucinate, there is no mind independent object of my perception (the pink elephant I perceive isn’t a physical pink elephant)

• c1) therefore, the object I directly perceive in a hallucination isn’t a mind independent object

• c2) therefore, direct realisms claim that I directly perceive mind independent objects and their properties is false

what is the argument against hallucinations - for direct realism - veridical perception argument 

• hallucinations are separate causes from ordinary (veridical) perception

• during a hallucination, we are directly perceiving the contents of our own mind, rather than the external world

• how can we tell if they’re indistinguishable from ordinary perception?

• P1) if they were indistinguishable, then we wouldn’t be able to recognise experiences as hallucinatory

• P2) we can identify experiences that are hallucinatory and those that aren’t

• C1) therefore, we must be able to distinguish hallucinations from genuine perceptions of mind independent objects, once we accept this the problem of hallucinations can be dismissed as we can separate hallucinations from ordinary perception and explain them as perceptions of our own minds

what is the counter argument for the veridical perception argument - against both hallucinations and illusions, vison blind spot

• anil seth

• science suggests that what we perceive is constantly affected by our mind and its expectations 

• this means that our mind changes our perception in a way that is indistinguishable from normal perception 

• example - our vision has a blind spot, meaning there is a gap in our veridical perception, we don’t percieve this gap because our minds fill it in with what it expects us to see based on our surroundings, therefore a portion of our vision (perception) is mind dependent

• argument against illusions as well as hallucinations - for example, the Muller Lyer illusions of the lines that look different lengths but are the same, there is nothing out there in the physical world causing this distortion, but it’s based on how our mind interprets things

• therefore, our mind’s expectations of what we will perceive affects what we actually perceive and that therefore we aren’t perceiving an external world directly but our interpretation of that world

the argument from perceptual variation - against direct realism - bertrand russle - table

• our perception of an object is always bound to our perspective

• there is no neutral vantage point from which to perceive reality

• p1) my perception of the table changes depending on the conditions under which it is perceived (e.g the angle changes the size, the light changes the colour)

• p2) the table itself always remains constant 

• c1) therefore, my perception of the table must be distinct and separate from the table itself

• the world cannot be exactly how it appears to us if it constantly changes depending on our perception of it - no two people will ever perceive the world the same way

argument against bertrand russle’s perceptual variation

• we can accept that our perception of the world is always different depending on how we perceieve it, but that doesn’t mean that the world we’re perceiving is distinct and seperate from us 

• we can see things such as our angle changing the size of an object or the light from which we view it changing the color as relational properties

• relational properties are properties that depend on the relationship between the object and the perciever 

• in russles table argument, we can say that the table looks darker under dim light, and that this is one of the properties that the table has

• we can directly perceive the object and its relational properties and even explain them using facts about light and vision 

what is the time lag argument - against direct realism

• our perception of objects depends on light being reflected from these objects and detected by our visual system (eyes)

• there is a time delay in the process of the light meeting our eyes, may be very small but could be extremely large in the case of objects that are very distant

• in case of some stars, for example, they will no longer exist by the time the light reaches our eyes

• we cannot perceive something that doesn’t exist, and yet we are percieving something in case of the star - must be something other than the star itself 

• therefore, direct realism is false, as it states that we percieve everything exactly as it is in the external world 

what is indirect realism? 

give an example of direct realism

• our perception of an apple is that it has the properties, small, round, red, crispy and sweet

• if our perception of an apple matches the properties of the object, we know that it must be real and mind independent

• the properties we perceive must in the apple itself, meaning if we didn’t perceive it it would still have those properties and would continue to exist

what is realism and anti realism?

r - the view that objects are mind independent - X appears outside of all human perception

a - the view that objects are mind dependant - X doesn’t exist out of human perception and neither does its properties

what is indirect realism?

• realist theory of perception, immediate obejcts of perception are MD objects that are caused by and represent MI objects

• objects in the world exist independantly of the mind, but these MI objects are not immediate objects of perception

• instead, we directly percieve sense data, which acts as a mediator between us and the EW 

• sense data is caused by and represents MI objects in the EW, gi,ves me an internal picture of the way the EW is 

• there is no guarantee that sense data is indenticle to the objects in the EW

• sense data creates a veil of perception between the EW and the perciver 

what is an example of indirect realism?

• you view a cat on the sofa

• you perceive a ‘sense datum’ of the image of the cat in your mind, but not the mind independent object that is the cat and the sofa

• they believe that the cat and the sofa exists independent of the mind but our perception of it is mediated by mental sense data

• therefore, the mental sense data gives us an image of the mind independent object, but doesn’t perfectly resemble it

give qualities of sense data

• it’s subjective to the perciver

• mind dependent - exists in the mind of the perciver

• private - only accesible by the perciver

• infalliable - not subject to doubt - you cannot doubt that you are experiencing those kinds of properties and objects, wether or not they are representative of what exists in the EW

problem for indirect realism - indirect realism leads to scepticism about MI objects 

• sense data allows us to infer the existence of objects that they accuratley represent, and this allows us to infer that the EW exists 

• however, this assumption that our sense data and therefore our perceptions are casually related to an EW cannot be supported from the perspective of an  indirect realist 

• the only way we can verify wether our perceptions are caused by external objects in the EW is by somehow checking this correspondence 

• however, i only ever experience my own sense data, so i cannot acess the EW, therefore i cannot verify that my sense data is caused by and accurately represents MI objects in the EW

coherence of various sense - lock and cockburn

• our sense data provides a complete and coherent picture in which all different senses all agree with each other

• locke - the different senses bearing witness to the truth of each others report concerning the existence of things without us, e.g - i see a mug of coffee with steam coming off it, when i drink it, it burns my tounge, these 2 senses are coherent with eachother, they match up to make a clear picture of the MI objects in the EW that sense data is caused by and represents

• cockburn - if a single sense changes, we cannot confirm that this change represents a real change in the EW, but if more than one sense changes similtaneously in a connected manner, this is likely to be caused by an underlying reality (the EW)

• experience teaches us that a change in one sense will lead to a change in another, if i sharpen a pencil it’ll both look and feel different - this correlation is consistent and suggests the existence of an underlying reality causing these changes, which we then experience through sense data

locke - involuntary nature of perception

• if all our perceptions are mind dependent, then we must have control over our perceptions

• however, we cannot simply bring perceptions/sense data into existence when we wish

• nor can we avoid having certain sense data

• we seem to be a passive recipient of sense data

• for example, i cannot taste chocolate cake whenever i want to, yet i can think about these things, and i cannot avoid percieving a rainy day and instead percieve a sunny one beacuse it is what i wish to percieve

• therefore, perception is not mind dependant and is more likely to come from a MI source, such as the EW

russell - the external world is the best hypothesis 

• russell accepts that the existence of sense data doesn’t prove the existence of the external world with complete certainty 

• there may be slight hypothetical doubt about the existence of the external world 

• however, the existence of the EW is the best hypothesis because of 3 points - it explains where my perceptions come from, how objects appear to exist and change without being percieved (cat walks across room and gets hungrier over time), and our ability to communicate about our perceptions with others, suggesting that we percieve the same things as them q

• therefore, we should not reject the existence of the EW, as our belief in it is instinctive, and we don’t have a better explanation to replace it with 

explain locke’s idea of primary qualities

• do not depend on human perception

• exist within the objects themselves and are inseparable from the object

• include properties such as size (extension), shape, motion, quantity

• essential to the object

• no matter how the object changes these properties will stay the same - therefore our experience of them accurately resemble them

• behave in the same way as they would in a world without percievers

• accesed by more than one sense

• have the power to create the perciever to experience secondary qualities

explains locke’s idea of secondary qualities 

• depend on the perceiver 

• not essential to the object 

• examples, colour, smell, taste

• represent but dont resemble the object 

• acessed by one sense 

• not ‘in’ the object 

• in a world without percievers, these properties wouldn’t exist 

what was berkeley’s attack on pq and sq?

• argued that the distinction between locke’s primary and secondary qualities didn’t hold up

• he argued that all qualities are mind dependant

• for example, size changes depending on perspective

• argues that all qualities are known to us through perception

we cannot know the nature of MI objects, because MD ideas cannot be like MI objects - berkeley

• attacking the indirect realist claim that sense data can represent the EW

• he claims that mind independant objects are too unlike mind dependant ideas, and that they cannot accuratley represent MI objects

• the MD ideas we perceive (sense data for indirect realists) are always changing, variable and in a state of flux, whereas physical objects would be fixed and constant

• how can circular sense data and oval sense data both represent an object that only has one shape?

• he’s employing his ‘likeness principle’- things can only tell us about other things that they are like

• therefore, sense data can only tell us about other sense data, they cannot tell us about MI objects that exist in the EW

locke, cockburn, russell and berkely - direct or indirect realistits?

locke - indirect

cockburn - indirect

russell - inidrect

berkely - direct