Seymour asked:

We all know, currently, it’s impossible to ‘scientifically’ or ‘physically’ go back in time. But if you had the dying urge to do so, say if you wanted to correct a critical mistake you made, and provided you would not disastrously change the cause of history by doing so, could the following be plausible: you are given a drug which puts you in a coma for the rest of your life. You have a dream in that coma that lasts from when you were knocked out until your real-life death. The events in the dream start the day before you do this bad thing, so you can do something different instead. So essentially, this drug simulates your life from a certain point until your death.

My question is, is this the same as going back in time in reality (‘scientific’ or ‘physical’ time travel)? Or even, is there a difference between the two? And, what’s more important, the ‘reality’ of life, or our interpretation of it, or are they the same (because everyone has different interpretations)?

Answer by Helier Robinson

It depends on what you mean by ‘the same’. If you mean similar then of course the dream and reality are similar, except for your not doing the bad thing. If you mean identical, or one and the same, then of course the dream is not reality: dreams never are. Similarity has a plurality of terms, identity has only one; and ‘the same’ is ambiguous about these. Secondly, what do you mean about the reality of life? Reality is usually defined as all that exists independently of what anyone believes about it, and beliefs about it are true if they are similar to it, and otherwise false. So reality and a belief (or interpretation) about it are two, cannot be one; so what do you mean about them being ‘the same’?

Helier Robinson is Emeritus Professor in Philosophy, University of Guelph. His books are available from http://SharebooksPublishing.com.

Answer by Geoffrey Klempner

Before I answer your question, a spoiler alert. Don’t read this if you haven’t seen (but are planning to see) the movie Vanilla Sky (2001) starring Tom Cruise and Penelope Cruz, a remake of the movie Open Your Eyes (Abre Los Ojos, 1997).

What you describe is basically the plot of Vanilla Sky. Honestly, I would much rather you saw the movie than read my answer (read the answer afterwards!).

OK, so we learn late in Vanilla Sky (warning, this is the big ‘reveal’) that much of what we thought was taking place in the life of the main character played by Tom Cruise, is actually a lucid dream. Following a disfiguring accident, he chose to be put to sleep, dreaming of the life he would have lived had the accident not taken place (he gets the girl, lives happily ever after, etc.). (This is a near-future where ‘dream machines’ have been developed.)

Unfortunately, things don’t go as planned, and the dream morphs into a nightmare, forcing Tom into the big decision to have himself woken up to face the consequences of his actions in his ‘real’ life.

And that’s the point. Regardless of how well the dream machine works, you can always be woken up. That’s one definition of ‘reality’. An experience isn’t ‘real’ if there is the possibility of one’s being woken up.

That opens a can of worms, however. What kind of ‘possibility’ is this? I can conceive of the possibility of ‘waking up’ after I have finished writing this answer, to find that I am a nine-footed purple monster on the planet Zog who dreamed of being ‘human’. Is everything we can coherently conceive (in what sense of ‘conceive’?) actually possible?

I once thought I had an answer to this question, but I am not so sure now. ‘Reality’ is just whatever we take reality to be now, and if we find we were wrong (we wake up) then we just revise our definition.

http://www.philosophypathways.com/vita.html

Marc asked:

My question concerns real vs. nominal definitions.

Would it be reasonable to say that the real definition of ‘tiger’ I have given is false? Assuming the earlier denotation of ‘tiger’ I gave by pointing to actual large, four-legged cats?

Answer by Helier Robinson

I assume that you mean a real definition to be a definition of something in reality and a nominal definition to be a definition in language. A real definition is then a special case of a nominal definition (since it can hardly be a definition if it is not put into words) while a nominal definition may have no reference to reality but still be a definition (such as a mermaid being half woman, half fish).

We can then say that all real definitions are true, and all false definitions are nominal definitions. Ostensive definitions (definitions by pointing) become real definitions by assigning them a word, such as tiger, or a phrase such large four-legged cat; but the phrase must be a true description: eight-legged invertebrate is a false description and so a merely nominal definition.

Helier Robinson is Emeritus Professor in Philosophy, University of Guelph. His books are available from http://SharebooksPublishing.com.

Answer by Geoffrey Klempner

Your question relates to the analysis of ‘natural kind’ terms, which was revived by Hilary Putnam and Saul Kripke in the 1970s. Originally, a distinction coined by Locke in his Essay Concerning Human Understanding the notion of a ‘real’ as opposed to a merely ‘nominal’ definition fell into disrepute — it had become associated with the supposedly ‘bad’ Aristotelian metaphysics of ‘substance’ and ‘essence’, notions that looked suspect when viewed from the perspective of post logical-positivist analytic philosophy.

In his landmark paper, ‘Naming and Necessity’ (published in book form in 1980) Kripke showed a way to make sense of ‘real definitions’ of natural kind terms. To take an often quoted example, Gold, defined nominally as a ‘yellow metal, etc.’ is in fact not yellow in its pure form, but white. Iron Pyrites (fools gold) is not gold even though it is yellow and looks metallic.

What is Gold? Anything with the same atomic structure of that (pointing to a sample of gold). We identify samples of elements, say (it could equally be samples of animal species, such as a Tiger) and define the term as anything ‘similar in the theoretically relevant way’ to that.

This procedure, however, is not assumption free. You have to assume that the story about the Periodic Table of elements is true. It may be difficult to see how we could be wrong about that, but there will be other cases of ‘real definitions’ of supposedly ‘natural kinds’ which get going only because of a theory which is in fact false. We thought we knew what ‘kind’ we were pointing to but we were wrong.

With the perspective of a few decades, it now looks to me that the whole issue of ‘real essences’ and the revival of the Aristotelian/ Lockean notion of ‘essence’ was a trifle over-stated. Yes, there is an interesting distinction to be made, in relation to the practice of science — the way things are grouped into theoretically significant kinds. But really a ‘real definition’ is just a more sophisticated ‘kind’ (from the perspective of logic) of ‘nominal definition’. The idea of a real ‘real definition’ — which gets right down to the metaphysical nitty gritty of things — looks just as suspect now as it did in the heyday of logical positivism.

http://www.philosophypathways.com/vita.html

Mike asked:

Hello, this question is about things that have happened in the past, experiences we have had and how we think about them.

Someone makes a decision that turns out to be a bad one, and you can say well if you made a better decision of course the universe would have unfolded differently and you would have had a better experience, a better life, but is that true? Is it possible to argue that whatever has happened, good or bad, had to happen because it actually did happen, and that’s all the proof you need. It doesn’t matter if the Determinists or Libertarians are right or wrong, it has nothing to do with a belief in fate, something happened in the past therefore it had to happen. The world wars happened, now we can look back with hindsight and see how they could have been avoided, but when you take into account all of the many and varied factors at the time that contributed to them isn’t it possible to say that they had to happen, how couldn’t they?

Answer by Jürgen Lawrenz

Let me recommend to you first, that you stop your indiscriminate jumbling of ‘the universe’ and ‘someone’. These things are not compatible. The universe is a big place and ‘someone’ a pretty puny speck of dust in the middle of nowhere. So let’s leave the universe alone, as none of us specks of dust genuinely know what is the case with it, and stick to what we can reasonably know in the context of your question.

Then the first item to be considered is a differentiation between things or events that are necessary, and those that are contingent. Now as you are speaking of humans, you are speaking of contingent things. Every act of every person is contingent, as ultimately only death removes choice (I’m not speaking of ethical or survival choices here). Therefore your claim that ‘it could not have happened any other way’ is false. If you had not written your question, I would not have written this reply. If you wish to claim that you were forced to write it, I don’t believe you. You weren’t dead when you wrote. QED.

Although this is ‘the short answer’, I don’t feel the necessity for a longer one, since only death terminates the process of learning. I believe you are confusing the unwillingness of humans to learn ‘better decisions’ with something else — maybe with our instinctual estate which frequently dominates our decisions and clouds our judgement. So the fact that something happened in the past is no argument for or against either determinism nor libertarianism. It is simply the contingent outcome of contingent occurrences; and each of these was a choice or a clutch of choices at the time.

For example, once you are in possession of certain facts, you would not fall for the easy trap you laid for yourself concerning the World Wars. Thus on the day before the outbreak of World War I, the Austrian High Command received three conflicting instructions from three government instrumentalities, two of which supported them in their intention of going to war, while one refused the support. The Austrians chose (repeat: chose) the supportive advice, whereupon they left the German government with egg on their collective faces. And now, in this contingency, the Germans felt they could not back out of supporting the Austrians who were already mobilising, without looking like idiots. So you can see in this example plenty of choices on both sides that were certainly not forced on anyone without a door standing open to retreat!

But I also want to give an example of choices which overturned the legal murder of hundreds of women in our civilisation, not all that long ago. These women were called ‘witches’ and supposed to be consorting with the devil. But when Descartes’ mechanistic philosophy gained its dominant standing in the latter half of the 17th century, it was gradually recognised that the commonly believed practises of witches (i.e. riding on a broomstick through the air) were physically impossible. In the outcome, by the choice of relevant authorities, witch burning was phased out quickly, after it had reached its unsalutary peak in Descartes’ own lifetime.

I hope you can see now that hammering away at the contingent facts of history as if they were pre-determined, is not a conclusion, but a fallacy.

Jürgen Lawrenz at philosophos.org

Dominique asked:

I’m interested in the implications of Arthur C Clarke’s third law ‘any sufficiently advanced technology is indistinguishable from magic’. Do you know of any philosophers who have addressed this? Can you recommend some reading? Thanks for your time.

Answer by Craig Skinner

Clarke’s laws appeared in his 1960s/ 1970s writings, although the third law appears in others’ writing at least as far back as 1866 (Rider Haggard).

Few people in our present culture explain things by magic. Even small children know that texting, drones, Google and so forth are wonders of science not magic. But no doubt if these were shown to a past (or present) culture prone to magical or supernatural explanations, the latter would be invoked to account for the marvels.

The key live philosophical discussion on advanced technology is the possible explosive increase in artificial intelligence (AI) and alleged risk of humanity being eclipsed. The story goes as follows. AI is steadily improving. Soon (years or decades) human level intelligence will be reached. This will be a no-way-back ‘singularity’ because these AIs will create even smarter robots, which, in turn, will produce yet smarter ones, quickly leaving homo sapiens behind, so that the activities of these superintelligences will be as opaque to us as quantum mechanics is to my dog, and they may have no place for us in their worldview, and eliminate us.

Discussion centres on whether this is possible, whether we could still be in control, whether we need to be proactive, whether morality could be built in to AI, whether the singularity has already happened and we are all simulations in an advanced AI’s virtual world.

Now to recommended reading. Much is not easy going, but it’s all great fun.

Recent debate was kick-started by David Chalmers’ 2010 Journal of Consciousness Studies (JCS) article ‘The Singularity, a Philosophical Analysis’ (I think it’s available online). This was followed by two 2012 JCS issues (Vol 19, No.1-2 and No.7-8) with numerous responses to Chalmers including those of Dan Dennett, Barry Dainton, Susan Blackmore, Susan Greenfield, Frank Tipler, Igor Aleksander, Ray Kurzweil, and Nick Bostrom. The latter has followed up with a terrific book, Superintelligence: Paths, Dangers, Strategies (OUP 2014).

Good luck.

Craig Skinner at philosophos.org

Derek asked:

What is the point of the Sorites paradox? I’m a regular listener of the Rationally Speaking podcast, and couldn’t help but notice that Julia Galef concludes ‘that philosophers think there should be a precise definition or a right answer’. I’m of the opinion that the point of the thought experiment is to help us realize the ‘messiness’ of language. Which of us is closer to the truth?

Answer by Jürgen Lawrenz

I wish I could help you with your first sentence. I can’t figure it out either, nor can I think of the slightest use of arguing such questions. One way of resolving the issue would be to look at the languages we speak and just acknowledge that they are full of paradoxical cliches for the simple reason, that they reflect the experience of their speakers over many generations; and you can be sure that none of them (at the primitive forefather stage) was ever concerned with asking ‘when is a heap not a heap anymore?’, or ‘when does blue paint shade into green as I keep adding drops of green paint?’ So you are certainly on track with your surmise of ‘messiness’.

I think this is the kind of imprecision that stings logicians like a nail in the toe. They can’t cope with the messiness of language use. The quote you offer from Julia Galef is plainly an opinion from that stable. Efforts to improve the logical structure of language have been going on for almost 200 years and all failed. I suspect the reason has to do with the fact that we learn our language as babies. Terence Deacon in his book The Symbolic Species offers the theory (based on years of studying in situ the emergence of creole speech at the intersection of two or more languages) that such new languages are created by children. So it seems that philosophers are not the right people to ‘fix up’ the spontaneous language behaviour of humans!

It seems to me that another issue plays into this problem. Our intuitive (spontaneous) apperception of a plurality is restricted by what our eyes can take in at one glance (and to some extent what our fingers can feel and our ears can separate among sounds). When you look at the stars, you’re looking at a heap. Stargazers over the millennia got around to ordering the stars into small heaps, like the Pleiades (seven stars). They are not really a group; but they form a heap that can be grasped instantly. This is because our eyes spontaneously group pluralities into small geometrical patterns up to 12. And now, when you look at our ancient number systems based on 12, you can discern in it a clear build up of clean geometrical patterns based on 2 and 3. With 13 and higher, intuition begins to wobble uncertainly and we start sensing heaps!

I guess this leaves the opposite issue unresolved, which perhaps should attract equal attention from logicians. When does a heap become a hump, a mound, a dune, a hill, a mountain? Can we have some quantifying precision to these expressions as well, please, while you’re at it?

Jürgen Lawrenz at philosophos.org

Yola asked:

What is the main argument on Bertrand Russell, ‘Appearance and Reality’? Explain why the argument is good (valid/ strong, sound/ cogent) or bad (invalid/ weak, unsound/ uncogent).

Answer by Danny Krämer

Philosophy is often a rebellion of thought. You find traditions that make no sense to you and you meet people whose arguments you just think are false. Often you even rebel against your own former beliefs. When Russell came to Camebridge British philosophy was idealist philosophy inspired by Hegel. One of the well known British followers of Hegel was F.H. Bradley. For these idealists the connection between beliefs and not the connection between thoughts and the world were important for truth. So they advocated a kind of coherentism. Everything that can be thought is a thought of someone and therefore everything that exists is either a thought of a universal mind, as in idealism, or it consists of many monadic minds, as Leibniz suggests. Russell, together with G.E. Moore, was one of the leading figures in the rebellion against British idealism.

The interesting thing in the first chapter of Russell’s Problems of Philosophy called ‘Appearance and Reality’ is his Cartesian starting point. He asks: Can we get a foundation for our knowledge that is so certain, that we can build our whole system of knowledge upon it? That is clearly a question that Bradley would reject. His form of idealist coherentism had no place for a foundation of any knowledge. Russell makes an empiricist point: In everyday life we have no problem in making true statements. We just observe state of affairs and then we know for example that the tomato is red. But he cautions us about any crude and naive empiricism. We often know that the things are not at all how they appear.

Take Russell’s argument from the relativity of perspectives:

Five persons stand around a table.

Every of this persons sees a little bit different colour shade and form of the table.
With some manipulation of the light even all five could see a different colour altogether.

Therefore there is not THE colour of the table.

What we call the colour of the table is just the colour of the table under normal circumstances to a normal observer. So it seams that the table itself has no intrinsic colour. The colour of the table is a relational property between the table, the environment and the observer. Russell suggests a ontology that can preserve the difference between appearance and reality. There are, he says, not only objects like tables but also sense-data. These are the things that are immediately known to us by sensation, like colours, sounds, smells etc. So the colour of the table is not a property of the table but a sense-datum.

Is the argument sound? I think it is as far as it goes but I don’t like Russell’s ontology of sense-data. The problem with sense-data as mental objects is that scepticism reigns supreme. If material objects just cause some mental objects which we perceive directly then this mental objects could be caused by a table or by a supercomputer to a brain in a vat. If we understand colours as relational and very complex properties between the observer, the object and the environment and not as sense-data i.e. mental objects between us and the object, we get a externalist and functionalist understanding of mental properties.

But Russell opened up the discussion for a new style of philosophy that was not idealistic. Pace the British idealists and some followers of Leibniz, there are material objects in the full sense of material. They are independent of any thoughts. Russell so clears the path for questions about meaning and reference, semantics, representation and so on, which are still with us.

Danny Krämer has a Philosophy MA from the university of Erfurt. His blog ‘The Realist Turn’ can be found at http://therealistturn.wordpress.com.