Philosophical Musings

Recently, I’ve been doing a fair amount of thinking about some semi-related aspects of philosophy. So I thought I would procrastinate further from my individual project and go into them here.

Time Travel

I should preface this section by saying that I doubt that time travel is possible at all. However I still like theorizing about how it would act if it was possible.

Ever since I read Harry Potter and the Methods of Rationality, I’ve preferred the theory of time travel that it proposes to the “Trousers of Time” theory. My problem with the latter is that it is based on the universe splitting into two possible timelines whenever time travel occurs, and both are causally inconsistent (in one, the travelling thing just disappears; in the other, it appears spontaneously).

The alternative that I’ve come to accept is a single-timeline theory where effect can precede cause. In this theory, at the moment that you go back in time, the thing which you are about to do has already happened (and you may well have seen the effects of it before you go back in the first place). This makes it possible for causal loops to occur, the only restriction being that any such loops are stable (paradoxes literally can’t happen).

Suppose you find a note with something random written on it in your own handwriting; you must then write that note yourself and go back in time and plant it for your past-self to discover. If you decided not to then you wouldn’t have received it in the first place, because that wouldn’t be a stable time loop (this has a tangential relation to the section on free will later on). Even more amazing is that whatever you wrote is information that came from absolutely nowhere! You could use this effect to do very difficult calculations, just find an algorithm that only creates a stable time loop for the correct answer to the problem. If you followed that algorithm you could find the answer in a single time-travel journey.

Now suppose you have a machine that applies these algorithms for you by sending some information back in time. If you gave it an algorithm which could only result in a paradox then the only thing that could possibly happen would be that the machine breaks somehow (since the laws of thermodynamics are purely probabilistic, this is always possible, it’s just usually prohibitively unlikely). To compensate for this, you could build in a fail-safe to the machine which just says “improbable” with a very low probability; for paradoxical results, this would still be more likely than the machine breaking. The main thing is, this machine can produce anything you like so long as your algorithm makes it the only plausible time loop.

What we have come up with here is very nearly a finite improbability drive! Unfortunately, in order for it to work time travel needs to a) work, and b) work like this. I still think that’s unlikely (especially since it would prove the universe is not Turing compatible), but we can dream…

The Nature of Reality

The nature of reality is something I’ve been interested in for a long time, and they have long been a popular topic of philosophical conversation, especially since films like The Matrix and (less well known) The Thirteenth Floor.

Fundamentally, it seems impossible to tell whether we are in a simulation or the “real world” (whatever that may be). However, there are things we can tell about this universe by observing it, such as the basic laws under which it operates. But there are some more properties we can also deduce, specifically one relating to consciousness…

Split Brain Patients are people who, to treat severe cases of epilepsy, have had the two hemispheres of their brain disconnected at the Corpus Callosum. These people were originally one consciousness, but now they are two. This has been demonstrated in numerous tests. To get an idea of the condition, try watching this video. Now, if a person has had a purely physical operation that splits their entire consciousness in two, the obvious conclusion is that consciousness is a purely physical phenomenon. We have just reasoned that we are not in The Matrix!

Of course, this was not a complete proof. The machines could be measuring exactly what happens to our brains inside the simulation and then using very advanced equipment to modify our real brains in exactly the same way, in order to trick us. They would also have to cope with a vast number of other conditions such as Alzheimer’s, mood swings with various causes, etc. Overall, I don’t think it is a plausible explanation for consciousness that it is imparted to us by another plane of existence, because the inner workings of our brains seem to be so tied to the laws of this one. It’s not impossible that it comes from another plane of existence, but eventually there must always be an explanation for how consciousness is built up. Since we can find reasonable explanations for all aspects of behaviour and decision making here and have no reason to suspect another plane of existence, we can ignore that possibility using Occam’s Razor.

Not only does this make it implausible that we are living in the matrix, it makes any sort of dualistic universe infeasible. This means that any notion of a soul that depends on another plane of existence is likely to be false. This section also relates heavily to the section on free will.

Free Will

You may assume that this section will have a large impact on your everyday life. However, it has very little impact on the decisions you make every day. Something that can effect things much more is the next section on Morality.

There are two viewpoints when considering free will: compatibilism and incompatibilism. Incompatibilism defines free will such that it is impossible to have it in a materialistic universe, essentially saying that for free will to exist we require some form of dualism; this is the viewpoint that people tend to assume when considering the question of free will. Compatibilism, on the other hand, says that as long as someone has the ability to make a decision, they have free will.

As outlined above, the evidence suggests we are in a materialistic universe. One obvious question is how it is possible for someone to make a decision in such a universe. I have recently discovered the answer to this in a course on Computational Neurodynamics: Take two networks of excitatory neurons and connect them each to a network of inhibitory neurons; then connect each network of inhibitory neurons to the excitatory network from the other side. This setup only allows one of these two sets of excitatory neurons to be active at a time. If we had a very simple creature which has to decide between two sources of food, at equal distances on opposite sides, we could connect sensors for its two different sides to each of the two excitatory networks, and then connect these excitatory networks to some method for moving towards the food source. This animal has just decided between two equal sources of food, and it was all due to tiny variations in the times that some neurons fired.

Essentially, this is an example of a decision being made in a materialistic universe (note: it does not have to be a deterministic universe; quantum randomness could exist without having any effect on free will). For the compatibilist, this equates to free will. However, for the incompatibilist, things get more complicated: Would there be free will if something random at the quantum scale caused a certain neuron to spike at a certain time and the decision to be made in one direction rather than the other? Inherently, there’s nothing more free about this than in a deterministic system, we are still bound to materialistic laws, even if they are random. I am currently of the view that an incompatibilist can only have free will in a dualistic universe (and even then, something in the other plane of existence must be causing the decisions somehow; if it has the same rules of cause and effect that we do then it will exhibit the same problem, the only way around this is to abandon cause and effect).

Morality

Is there an objective standard for morality? The universe as a purely materialistic system seems to imply that there is not. Consider that any action is merely the result of a large set of previous actions beginning at the big bang; it follows that no responsibility can objectively be assigned to the person performing the action, since they were merely a product of their genetic code, culture, and everything they have ever experienced.

Yet we still give people responsibility for their own actions. I posit that this is because we are either genetically or culturally programmed to assign responsibility to people. Ultimately, it would not be useful to assign responsibility for something to the entire way the universe has unfolded. We generally see people as responsible because it affects our feelings about them, and we may wish to thank them for a good action or punish them for a bad one.

Fundamentally, morality seems to stem from group selection during evolution: if you are altruistic towards your kin, they are more likely to survive and pass on the genes that they share with you. This can easily explain from an evolutionary perspective why we find such things as murder completely immoral: it decreases the species’ chances of survival. There will be similar explanations for other aspects of morality that we evolved with. However, there are also aspects of morality that are much more modern and we could not have evolved with, such as whether or not using asbestos as insulation is a good idea. These can draw on more basic instincts, but additionally there is a sort of moral Zeitgeist that gives us a sense of the morality of a society, which we each build up through communication with others. We would not know that asbestos was bad if nobody had told us about it.

That was a lot of writing. Hopefully someone finds it at least somewhat interesting. I’m definitely not an expert on any of these subjects, so I’ve probably made lots of mistakes and bad generalisations. If you found any, please point them out and prove me wrong.

3 thoughts on “Philosophical Musings

  1. Ben Harcourt

    Firstly: you receive an ‘Above average sense in a coder rambling about philosophy’ award sticker. Please forgive the following paragraphs of (hopefully correct) pedantry.

    = The Nature of Reality =

    “Now, if a person has had a purely physical operation that splits their entire consciousness in two, the obvious conclusion is that consciousness is a purely physical phenomenon.”

    This, I feel, is something of a logical fallacy – you skirt around saying so in the next few paragraphs, but go on to say that a Dualistic universe is infeasible. Consider for a moment a body standing in a shallow bath, and the statement:
    “Now, if a person has had a purely under-water operation that splits their entire consciousness in two, the obvious conclusion is that consciousness is a purely under-water phenomenon.”

    The point I am trying to make here isn’t very clear from this example, but it goes something like this:
    If we accept dualism*, then consciousness exists primarily as mind stuff. This does not preclude the consciousness’s presence in physical reality – in fact, the joined presence is one of the potential solutions for the agent problem.

    You’d arguably be better off from the standpoint that physics appears to be causally closed, which makes it impossible to solve the agent problem, as non-physical agents can not cause a change in physics.

    *For others: in monism, there is only a physical reality, so the point is moot.

    = Free Will =

    See http://harcourtprogramming.co.uk/blogs/benh/2010/08/to-what-extent-if-any-is-free-will-compatible-with-determinism/, the essay I did on this for my last philosophy class. It’s not a _good_ essay, I’m afraid. I have also other post, entitled “Blood”, which tends towards the conclusion that it doesn’t really matter whether we have what we would call free will. This section of the comment may, or may not, be a shameless plug.

    = Morality =

    Ah, tough one this. You can play all sorts of logic and maths games in an attempt to describe the meaning of this question, although none that derive nicely into a generic form (that I’ve come across).
    That said, if you cut right/wrong, good/bad out, and remember that all effects have a cause, then you can already have the assignment of blame*. Add in the concept of advantages to people, and you can start defining a framework for interactions in that sense.

    Morality, then, is just the (strange?) idea that actions should work to give as many people as possible advantages…

    * Blame being used in the sense that git uses it – find the person who caused this to be.

  2. Will

    Time travel – flarghargh it’s impossible given all our current theories of reality. I’d try to think up a new one, but it seems like rather a large outlay of effort for a sci-fi plot device. Actually, it might pave the way for actual, honest-to-god time travel, mightn’t it? Can’t be arsed anyway.

    The nature of reality – I originally thought your concept of what the Matrix might be was too restricted, but then I realised – why a brain in a jar? Surely the spinal cord too. And thus, the rest of the nervous system. And thus, the rest of the flesh. Then, it makes no sense to preclude the immediate physical world (since what are we but matter – no duality!), and thus the entirety of existence. So, ‘the Matrix’, if we’re in one, must be a simulation of everything. If there’s no way of telling if what we’re in is a simulation or not, there’s no way to tell if there’s an afterlife. I was going to say this translates to not having to worry about divine retribution in an afterlife, but maybe religious experiences are glimpses at whatever lies beyond? And it’s not impossible that these glimpses are not just forced on the experiencer, but orchestrated, and the orchestrating agent would thus be known as God?

    Free will – yeah, it only really makes sense if some part of the free will-having agent is outside of the system, doesn’t it?

    Morality – thoughts of this sort have lately made me think we ought to have a much better vocabulary for distinguishing actual intent, stated intent and actual action. Why don’t we have a word for ‘a lie told to oneself’?

    I am way better at this stuff when I’m slightly drunk, it seems.

  3. Anthony

    @Ben
    Yay, I like stickers. Thanks for the critique – I’ll try to respond to it sanely, please tell me if I fail.

    = The Nature of Reality =
    I think you’re right about it being a logical fallacy. I’ve also argued in the past that since energy cannot be created or destroyed, it’s impossible for anything non-material to affect anything material (it would have to create or destroy at least gravitational energy to do so), which amounts to the universe being causally closed. In fact, I think I like that argument better.
    I think I posted this one partly because I’ve been considering it recently, and partly because it makes it easier to understand the requirements of a dualistic universe. The argument was meant to be a sort of reductio ad absurdum, except the result isn’t logically impossible, it just seems intuitively silly.
    I did make sure to point out that it didn’t constitute a proof, but since the field of neuroscience can explain decision-making and how different areas of the brain perform different functions in a purely materialistic universe, I feel that dualism is an unnecessary increase in complexity.
    However, most importantly, what this does prove is that there is no single seat of consciousness.

    = Free Will =
    We seem to agree on most points here. The main difference I can see is that I’m not convinced that randomness can allow for free will if you’re an incompatibilist. Even if a physical system can set itself up to be decided by a random event, that random event only adds randomness, not any particular objective agency behind a given decision.

    = Morality =
    You’re right, there are lots of ways of posing the question (Sam Harris has some interesting ideas about how you can try to find a set of morals which are objectively the best by hill-climbing across a moral landscape). The main thing is that the universe doesn’t force a morality on us, and without us would be essentially amoral.
    I’m not sure that you can objectively define blame as the single person who caused an event, since they were themselves the result of interactions of lots of other things. Since X is to blame for A, and X only happened because of Y, why should we not blame Y for A? Then you can apply this transitively until you get to the start of the universe.
    I think we have to define blame in any given situation for ourselves. While this is usually the most recent person to be involved in the situation, it can also be attributed to someone who paid them to do it, or their parents for raising them badly, or any number of other causes. e.g. “Sorry I didn’t get my project done, I blame Tim Berners-Lee for inventing the internet which I posted this blog entry on, which distracted me.”

    @Will
    Time travel – It’s not inconceivable, the main obstacle is that it’s not Turing compatible (i.e. you can’t use a Turing machine to simulate it in real time). However, it’s possible that the whole universe (including the time dimension) is the output of a massive computation which finds a solution to how things would play out given some laws of physics. I guess the main obstacle internally is finding a way to send things back in time, which probably isn’t possible, but since we don’t know how the universe works on a fundamental level yet, we can’t necessarily rule it out.

    The nature of reality – I’m not quite sure what you mean here. If the Matrix is a simulation of everything, then there’s no difference between the reality and the simulation. Also, even if we are in a simulation, upon death the reality behind it would have to follow the same pattern as the simulation in order for the simulation to produce correct results. This would mean that the real brain would have to die as well, meaning that there is no way for an afterlife to occur by simply “unplugging” someone.

    Free will – If you’re an incompatibilist, then yes, which would also make free will impossible in a causally closed universe. I’m more of a compatibilist, though that’s completely up to the definition of free will you want to use.

    Morality – I think it would be hard to vocalise an actual intent without it becoming a stated intent. I think for the most part English does ok, but things can get a bit verbose occasionally.

    It seems I’m better at this stuff during the early hours of the morning, or maybe that’s just when I usually write about it…

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.