Do ghosts exist?

It's not uncommon - even in this day and age - that we carry on to find genuine belief in the existence of ghosts. Even in cultures and populations where the belief that ghosts definitely exist isn't popular, agnosticism about the existence of ghosts is probably still prevalent. By people being agnostic, I mean that they do not reject the possibility that ghosts can exist. But with all the facts that we know about the universe available today, shouldn't we be able to reach - with some certainty - a conclusion regarding the existence of ghosts? With some amateur philosophical 'maneuvering', I attempt to demonstrate here that we have very good reason to believe that ghosts, or at least ghosts according to a particular conception, do not exist.

Casper the Ghost (Photo courtesy: maditsmadfunny.wikia.com)

Of course, to do this we need to start with a conception, or a definition of a ghost. Here are some properties - off the top of my head - which we may attribute to a ghost:

• A ghost is immaterial (non-physical)
• A ghost at least partly consists of some element of a person who was once alive but is now dead
• A ghost may also be conceived as the spirit,  consciousness, or soul of a dead person. 

The essential idea is that a ghost must be - whatever it is - a non-physical thing, and at least part of it belongs to an once alive person. Now let's get on to the analysis. 

To start off: what does it mean for something to be non-physical? It doesn't answer the question to simply list examples of things which are non-physical (e.g. God, mind, numbers), because these things do not tell us anything about the label 'non-physical'. Perhaps, we can understand something to be non-physical if it does not react (causally) with known physical laws. What this means is that a non-physical thing is not described by physical laws, and it is in a completely different realm from the physical world. A non-physical thing can do whatever it likes in the non-physical world, but it cannot in any way change how the physical world works. 

However, if that is true, all those ghost-featuring movies must have made a horrible mistake: EITHER ghosts are physical, OR ghosts cannot have any interactions with anything in the physical world at all. (We wouldn't have to worry about ghosts hiding in our bedrooms, because they cannot do anything physical to us)

Ghost (1990): Sam Wheat kissing Molly Jensen in this classic scene as a ghost. (Photo courtesy: tasteofcinema.com)

So, what if ghosts are physical? In my opinion, that doesn't seem to be a good way out either. To be physical, ghosts must react causally with our known physical laws. Unless we're willing to admit that physics   has gotten its fundamentals terribly wrong, it isn't consistent to hold the beliefs that ghosts can do certain things they do (e.g. alter mass, occupy no space, not made up of atoms). But remember, the knowledge of physics that human beings have built up over history has given us so much predictive success with the physical world: with that knowledge, we are able to land on the moon, send instant messages across the globe and split up atoms to create horribly powerful weapons of mass destruction. Is it really plausible to think then that ghosts exist?

Perhaps a few good rejoinders can still come from those 'ghost realists' (just made up this term to refer to those who think that ghosts exist). Firstly, realists may concede that ghosts cannot causally interact with the physical world. Okay, ghosts cannot move doors and make creepy weeping noises. But the fact that ghosts cannot interact physically does not stop ghosts from causally interacting with us in the mental realm! Effectively, this is saying that ghosts can and only can affect us psychologically. It would be more plausible then, to understand a ghost as a mental entity, something like numbers and concepts (or *beliefs?!). But would you say that numbers or concepts exist? But that is a much bigger question to deal with... (the question of whether mental things exist [not as in crazy, silly]).

The second (much less satisfactory) way that 'ghost realists' can respond is to say that ghosts are still physical, and they are still constrained by physical laws. This strategy allows us to understand ghosts as physical entities, but they would be much less robust as the 'ghosts' we know from movies and stories. Their 'status' would be equal to any other physical thing - humans, amoebas, tables, and the like - except that they are not living things! You can insist that this is true, but this approach offers a very poor and bizarre explanation of the universe, and it is largely inconsistent with what we already know about the universe.

So what's the verdict? Do ghosts exist? That very much depends on what type of ghosts we're talking about...

• Physical ghosts (highly unlikely)
• Non-physical ghosts capable of physical interactions (impossible; unless we define physical differently)
• Psychological ghosts (possibly; but even if they do exist, they would be as real to the same extent that numbers are real: "it's all in the mind")

Q.E.D.

*I hesitate to compare ghosts with beliefs, because beliefs are thought to have physical counterparts by some thinkers. 

Posted with Blogsy

Some Thoughts About Morality II

In Some Thoughts About Morality I, I discussed briefly about the origins of 'right' and 'wrong' and what follows from adopting the view that we ought to act morally because it follows from intuitions (conscience). I ended the post with an introduction to the "evolutionary" theory of morality, giving neither a clear nor comprehensive account of what it is about. 

As I was writing Some Thoughts About Morality I about five months ago, frankly I was at that point unaware of the literature in Evolutionary Psychology.* While I was quite illuminated by some of the material that I then came across, I will try to present my initial idea here in a non-scholarly way as I had originally intended.** 

The original "evolutionary" theory of morality is this. The claim is that there is no intrinsic value to morality, i.e. morality is not something that's good only for its own sake: morality is good only insofar as it contributes to the reproductive fitness of human beings as a group.*** The very rough idea is that if you assume there are two types of human beings in the world: (1) moral, altruistic ones versus (2) immoral, selfish ones, Group A with more moral individuals will have more reproductive fitness than Group B with more selfish individuals.

The red dots represent altruistic/moral individuals, while the blue dots represent the selfish/immoral individuals. The claim is that Group A (with moral individuals) is more likely to survive through natural selection. 

Why is this so? What is the evidence? One good reason that can be given is that such a picture of morality seems to best explain a lot of the following phenomena:

• Altruism and selfishness (or moral and immorality) is found across all societies. 
• Feelings about right and wrong (i.e. conscience) are universally found across cultures. 
• The apparent lack of a rational basis for morality. For instance, it is difficult to give a good fundamental reason for doing something morally than not. Also, how often do you feel that there are just no right answers to certain moral debates, regardless of by how much our scientific knowledge will advance?
• Why our conscience seems to emerge "naturally" like our ability to develop thought. Just think how feelings of guilt and compassion (can) emerge in humans without learning.

The plausibility of the "evolutionary" picture of morality lends support to the view that it is indeed representative of how the world really is. Interesting, such a picture of morality also fits well into the "Stag Hunt" example in Game Theory. The Stag Hunt example illustrates a situation where two individuals are always better off if they work together: if Jack and Jill go hunting separately (defect), they'll only manage to catch a rabbit each; if they cooperate and hunt together, they'll be able to catch a whole stag (which we'll assume that half a stag is way better than one rabbit). 

This table shows that cooperating is always the best outcome for the two individuals in a Stag Hunt game. (Photo courtesy of Wikimedia Commons)

Analogously, in the evolution story, what seems to have arisen is that individuals are always better off  together if they act morally. This includes not killing or injuring each other and not to act in ways which endanger the whole group (which is why we hate traitors). This is why Group A is more likely to survive than Group B: acting cooperatively increases their survival chances. 

Quick note: the reason why we still have selfish and evil individuals now may be due to the fact that the system fails to effectively "prune" the free-riders and those who are good at cheating. It's not difficult to see how living in a group large enough and possessing cheating skills good enough prevents these guys from being kicked out of the group. They get to enjoy the benefits of being in a moral society without being moral themselves.

But that's enough about evolution. IF this picture is true - what does all this say about morality? Should we be moral, just because we are born with a conscience? I suppose what all this tells us - if it is true - is that if we really want to fit a picture of morality with the rest of our knowledge about the world (particularly, scientific knowledge), we might need to resort to treating morality as something that is great as a means to an end. Psychologically, believing in this picture may lead us to treat morality less seriously, and we'll be worse off because society as a whole may become more selfish. To some extent, the "moral fabric" of society - what keeps humans working well together - relies most humans on NOT believing in this picture, grounding morality on something like "natural rights" or religion. 

Hey, isn't this an example where "ignorance (of some) is bliss (for everyone)"?

Speculative? Blasphemous? No, I don't think one post is enough to give a very comprehensive discussion of this fascinating issue. In a further post, I shall talk about Gyges' Ring and how this picture of morality fits into the story. 

*See this primer on Evolutionary Psychology by Cosmides and Tooby.

**Not to be mistaken as indicating my laziness to cite and quote /_/ 

***Reproductive fitness is measured by the number of offsprings. 

Potentially good idea: eliminating the a priori/a posteriori distinction

This is going to be one of those posts where I propose an unorthodox and highly radical idea and I give a completely insufficient and non-robust defense of it. I think I attempted something similar with moral realism in one of my previous posts before. This time, it's on the a priori/a posteriori distinction.

Typically the a priori/a posteriori distinction is understood as applying to propositions: an a priori proposition is one where its truth is knowable independent of (or prior to) experience. Philosophers usually point to propositions in geometry and mathematics, such as 'the internal angle of a triangle is equivalent to the angle of a straight line' or '2 is the positive square root of 4' for examples of a priori propositions. 

Conversely, an a posteriori proposition is one where its truth is knowable in virtue of experience. The proposition that 'Black swans exist in Australia' is an example of an a posteriori proposition, as one can only find out whether this proposition is true by visiting Australia and checking if there really are black swans in Australia. Claims made in the natural sciences are generally a posteriori.*

Now, this distinction may seem pretty unproblematic at first, for it's pretty obvious what most propositions fall under which category under the distinction. This distinction is also uncontroversial (for what I know), as it is so often used in arguments even in contemporary philosophy. But as long as the definitions of a priori and a posteriori I stated above are used, I think the distinction is problematic because it is based on the notion of experience.

Why is the notion of experience a problem? The reason why I think it causes problems for the distinction is our uncertainty of what experience refers to when we ask the question of 'what is experience'. Let's look at two possible definitions of the word:

1. Experience refers to what is felt, seen, heard, tasted or smelled, i.e. information available to the five senses)
2. Experience refers to whatever that is made available to the consciousness.

In general, the use of the distinction inclines towards the understanding of experience as in (1). With (1), however, you can get some pretty awkward results. Firstly, if experience is whatever that is available to the five senses, and assuming that the five senses are the only inputs to a person's experience, wouldn't it follow that all propositions are a posteriori? (Otherwise, where would the new data for the proposition come from?) Think about geometry: how do we come to have a concept of circle, or a line? Aren't they initially abstracted from the things we perceive with our five senses in the world? If there is no such thing as an a priori input, then what does the distinction mean at all?

The sun (left) and a circle (right): is it not a better explanation to say that the circle is abstracted from a natural object like the sun, then to say that we are born innate with the concept of a circle? (Left photo taken from Oia, Santorini)

Perhaps - as an immediate reaction - you're thinking about something like this: no, it's not like that; this understanding of the mind is too simplistic. Instead, one should think of the mind as having the five inputs but these five inputs are constrained by the structure of the mind. In other words, (under this view) there is no pure untainted inputs that we can get from our experience; the structure of mind make our percepts a certain way. For instance, without the mental structure that allows us to categorise things, we would not be able to individuate between things and hold the concept of a circle as an object. Without the innate principles of logical inference, we cannot infer that if P & Q is true, then P is true. In that case, you may argue that there are actually six senses: smell, vision, hearing, touch, taste and the innate structure of the mind which constrains and structures these senses. While the very last sense may seem very different from the rest, it is nonetheless an input because it contributes to our total knowledge. To end this rejoinder: if we do have six different types of input, then the a priori/a posteriori is still meaningful under definition (1). 

My second problem is this: if I am to take the view of the mind made by this rejoinder, then ultimately I will have to resort to definition (2). If every input into our mind from the five senses are cross-influenced by the sixth input into our mind, then in what sense does it mean when we say that we can classify the truth of propositions into ones knowable independent of experience and ones knowable in virtue of experience? If the innate mental structure input is part our experience, what does it mean to distinguish between a priori and a posteriori?

Picture according to definition (2) of experience

At first glance, I think my argument would most likely be rebutted by analysing the word knowable in the definition. Does that really improve the situation? I'll get to this in another post. 

*For a more detailed introduction on the distinction, I'd recommend David Papineau's (2012) book Philosophical Devices, Chapter 4.3. For now, my brief explication should be sufficient.

Posted with Blogsy

Some Reflections on Philosophical Work: Fruits and Purposes

I am now typing up this post at the Dubai International Airport, as I wait for my transit flight. It's a three hour wait approx., and I thought that it's about time I do some serious 'teleological' reflection.

If you've read a good sample of my other posts in this blog before, you may find this more 'personal' (or less dry and boring, as I occasionally am aware of are adjectives that can aptly apply to my other posts). So hopefully this would be a change for good. But let me first post a brief update on what I've been doing. At this point, I've:

• just spent ten weeks in London on a taught Master's programme in Philosophy,
• (and as a result of that) spent a huge sum of money which may be better off invested in a randomly selected stock from the FTSE;
• remained effectively unemployed and made little progress in developing any substantial career plans;
• on a more positive note, learnt about the philosophical issues and debates which crop up in the fields of psychology and biology. (under the heading philosophy of psychology and philosophy of biology)

So perhaps the thing that's bugging me is this: what exactly have I been trying to do? I know I'm trying to learn and engage myself in these interesting philosophical debates as possible, but what good is all that? Let's say I'm not in it for the money; let's say I'm doing these intellectual pursuits to create new knowledge for mankind. But what good is philosophy of psychology to the field of psychology, and what good is philosophy of biology to the field of biology? If I am neither a practicing psychology nor biologist, then is what I do purely for the satisfaction of my own curiosity? In that case, it would seem awfully selfish of me to spend so much money (originally belonging to people who funded my degree out of love) and time where the only reward is my pleasure.

Maybe I'm just thinking about the quote that's often attributed to Richard Feynman, that "philosophy of science is as useful to scientists as ornithology is to birds." But I think the worry goes deeper. If all of philosophy is like that (i.e. pretty damn useless), then I do kind of feel like I'm just climbed many rankings on the World's Biggest Idiots for spending so much time thinking about these philosophy problems.

There are two obvious strategies to get out of this pessimistic whatever-you-call-it. First, it's always more-or-less comforting to cite the instrumental advantages of doing philosophy, e.g. enhanced ability to talk about a wide range of subjects, improved critical thinking abilities, knowledge of the history of ideas and so on. But even so, all of this doesn't seem to warrant the time and money spent doing philosophy - if these are the only rewards of philosophy - because it seems pretty probable that you can get such abilities or knowledge cheaper and quicker by other means. Hence, I'm going to need a more 'robust' purpose for what I do.

The second strategy then, is to stubbornly insist that there's nothing wrong with investing in an activity that is intrinsically valuable, or an activity that is good even if it brings no other obvious reward. An example of this - maybe - is sex; people enjoy and have no problem doing it, even if it's not for some higher purpose. Personally I'm not too keen on justifying doing philosophy by comparing it to sex, but this strategy seems somewhat just better than the first one. Maybe a better parallel is music, which people really enjoy for its own sake; but I can't say for sure if music students do not sometimes ponder or doubt the purposes of their undertakings.

OR maybe - philosophy can really yield 'solid' intellectual fruits. It's probably true that philosophy may not produce any 'positive' knowledge like Newton's Three Laws. But if you see philosophy as the activity of conceptual analysis, then you can still get 'negative' knowledge by eliminating problematic concepts and bad inferences. You probably won't ever end up with a really good model or theory about anything in philosophy, but all the critical and analytical work can help you identify WHAT would not be a good model/theory. Perhaps then, this could be a really good motivation for philosophy besides its 'pleasure' value.

...But how well can philosophy SHOW beyond question the falsity of theories? If it leaves plenty of room for debate, then one may as well accept philosophy to be merely a 'fun intellectual activity for ages 3 or above'...

Posted with Blogsy