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All the ideas for 'On the Question of Absolute Undecidability', 'A Discourse on Method' and 'The Metaphysics of Scientific Realism'

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53 ideas

1. Philosophy / D. Nature of Philosophy / 1. Philosophy
Slow and accurate thought makes the greatest progress [Descartes]
     Full Idea: Those who go forward only very slowly can progress much further if they always keep to the right path, than those who run and wander off it.
     From: René Descartes (A Discourse on Method [1637], §1.2)
     A reaction: Like Descartes' 'Method'. This seems to place a low value on 'nous' or intuition.
1. Philosophy / D. Nature of Philosophy / 7. Despair over Philosophy
Most things in human life seem vain and useless [Descartes]
     Full Idea: Looking at the various activities and enterprises of mankind with the eye of a philosopher, there is hardly one which does not seem to me vain and useless.
     From: René Descartes (A Discourse on Method [1637], §1.3)
     A reaction: Well, yes. The obvious retort is that everything is vain and useless; or if not, then certainly metaphysics is. Useful for what? Is ornamental gardening useless, or sport? Art? What is the use of cosmology? He's right, of course.
Almost every daft idea has been expressed by some philosopher [Descartes]
     Full Idea: There is nothing one can imagine so strange or so unbelievable that has not been said by one or other of the philosophers.
     From: René Descartes (A Discourse on Method [1637], §2.16)
     A reaction: Actually I think that extensive areas of logical possibilities for existence remain totally unexplored. On the other hand, most of the metaphysical beliefs of most of the human race, including the majority of philosophers, strike me as being false.
1. Philosophy / E. Nature of Metaphysics / 1. Nature of Metaphysics
Metaphysics aims at the simplest explanation, without regard to testability [Ellis]
     Full Idea: The methodology of metaphysics... is that of arguing to the simplest explanation, without regard to testability.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 1)
     A reaction: I love that! I'd be a bit cautious about 'simplest', since 'everything is the output of an ineffable God' is beautifully simple, and brings the whole discussion to a halt. I certainly think metaphysics goes deeper than testing. String Theory?
2. Reason / A. Nature of Reason / 4. Aims of Reason
Methodical thinking is cautious, analytical, systematic, and panoramic [Descartes, by PG]
     Full Idea: Descartes' four principles for his method of thinking are: be cautious, analyse the problem, be systematic from simple to complex, and keep an overview of the problem
     From: report of René Descartes (A Discourse on Method [1637], §2.18) by PG - Db (ideas)
2. Reason / F. Fallacies / 4. Circularity
Clear and distinct conceptions are true because a perfect God exists [Descartes]
     Full Idea: That the things we grasp very clearly and very distinctly are all true, is assured only because God is or exists, and because he is a perfect Being.
     From: René Descartes (A Discourse on Method [1637], §4.38)
3. Truth / A. Truth Problems / 8. Subjective Truth
Truth is clear and distinct conception - of which it is hard to be sure [Descartes]
     Full Idea: I take it as a general rule that the things we conceive very clearly and very distinctly are all true, but that there is merely some difficulty in properly discerning which are those which we distinctly conceive.
     From: René Descartes (A Discourse on Method [1637], §4.33)
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Mathematical set theory has many plausible stopping points, such as finitism, and predicativism [Koellner]
     Full Idea: There are many coherent stopping points in the hierarchy of increasingly strong mathematical systems, starting with strict finitism, and moving up through predicativism to the higher reaches of set theory.
     From: Peter Koellner (On the Question of Absolute Undecidability [2006], Intro)
'Reflection principles' say the whole truth about sets can't be captured [Koellner]
     Full Idea: Roughly speaking, 'reflection principles' assert that anything true in V [the set hierarchy] falls short of characterising V in that it is true within some earlier level.
     From: Peter Koellner (On the Question of Absolute Undecidability [2006], 2.1)
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
We can base logic on acceptability, and abandon the Fregean account by truth-preservation [Ellis]
     Full Idea: In logic, acceptability conditions can replace truth conditions, ..and the only price one has to pay for this is that one has to abandon the implausible Fregean idea that logic is the theory of truth preservation.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 1)
     A reaction: This has always struck me as correct, given that if you assign T and F in a semantics, they don't have to mean 'true' and 'false', and that you can do very good logic with propositions which you think are entirely false.
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
We have no argument to show a statement is absolutely undecidable [Koellner]
     Full Idea: There is at present no solid argument to the effect that a given statement is absolutely undecidable.
     From: Peter Koellner (On the Question of Absolute Undecidability [2006], 5.3)
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
There are at least eleven types of large cardinal, of increasing logical strength [Koellner]
     Full Idea: Some of the standard large cardinals (in order of increasing (logical) strength) are: inaccessible, Mahlo, weakly compact, indescribable, Erdös, measurable, strong, Wodin, supercompact, huge etc. (...and ineffable).
     From: Peter Koellner (On the Question of Absolute Undecidability [2006], 1.4)
     A reaction: [I don't understand how cardinals can have 'logical strength', but I pass it on anyway]
6. Mathematics / B. Foundations for Mathematics / 1. Foundations for Mathematics
Mathematics is the formal study of the categorical dimensions of things [Ellis]
     Full Idea: I wish to explore the idea that mathematics is the formal study of the categorical dimensions of things.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 6)
     A reaction: Categorical dimensions are spatiotemporal relations and other non-causal properties. Ellis defends categorical properties as an aspect of science. The obvious connection seems to be with structuralism in mathematics. Shapiro is sympathetic.
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / d. Peano arithmetic
PA is consistent as far as we can accept, and we expand axioms to overcome limitations [Koellner]
     Full Idea: To the extent that we are justified in accepting Peano Arithmetic we are justified in accepting its consistency, and so we know how to expand the axiom system so as to overcome the limitation [of Gödel's Second Theorem].
     From: Peter Koellner (On the Question of Absolute Undecidability [2006], 1.1)
     A reaction: Each expansion brings a limitation, but then you can expand again.
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / g. Incompleteness of Arithmetic
Arithmetical undecidability is always settled at the next stage up [Koellner]
     Full Idea: The arithmetical instances of undecidability that arise at one stage of the hierarchy are settled at the next.
     From: Peter Koellner (On the Question of Absolute Undecidability [2006], 1.4)
7. Existence / B. Change in Existence / 2. Processes
Objects and substances are a subcategory of the natural kinds of processes [Ellis]
     Full Idea: The category of natural kinds of objects or substances should be regarded simply as a subcategory of the category of the natural kinds of processes.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 3)
     A reaction: This is a new, and interesting, proposal from Ellis (which will be ignored by the philosophical community, as all new theories coming from elderly philosophers are ignored! Cf Idea 12652). A good knowledge of physics is behind Ellis's claim.
7. Existence / B. Change in Existence / 4. Events / c. Reduction of events
A physical event is any change of distribution of energy [Ellis]
     Full Idea: We may define a physical event as any change of distribution of energy in any of its forms.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 2)
     A reaction: This seems to result in an awful lot of events. My own (new this morning) definition is: 'An event is a process which can be individuated in time'. Now you just have to work out what a 'process' is, but that's easier than understanding an 'event'.
8. Modes of Existence / B. Properties / 5. Natural Properties
Physical properties are those relevant to how a physical system might act [Ellis]
     Full Idea: We may define a physical property as one whose value is relevant, in some circumstances, to how a physical system is likely to act.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 2)
     A reaction: Fair enough, but can we use the same 'word' property when we are discussing abstractions? Does 'The Enlightenment' have properties? Do very simple things have properties? Can 'red' act, if it isn't part of any physical system?
8. Modes of Existence / B. Properties / 6. Categorical Properties
I support categorical properties, although most people only want causal powers [Ellis]
     Full Idea: I want to insist on the existence of a class of categorical properties distinct from causal powers. This is contentious, for there is a growing body of opinion that all properties are causal powers.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], Intro)
     A reaction: Alexander Bird makes a case against categorical properties. If what is meant is that 'being an electron' is the key property of an electron, then I disagree (quite strongly) with Ellis. Ellis says they are needed to explain causal powers.
Essentialism needs categorical properties (spatiotemporal and numerical relations) and dispositions [Ellis]
     Full Idea: Essentialist metaphysics seem to require that there be at least two kinds of properties in nature: dispositional properties (causal powers, capacities and propensities), and categorical ones (spatiotemporal and numerical relations).
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 3)
     A reaction: At last someone tells us what a 'categorical' property is! Couldn't find it in Stanford! Bird and Molnar reject the categorical ones as true properties. If there are six cats, which cat has the property of being six? Which cat is 'three metres apart'?
Spatial, temporal and numerical relations have causal roles, without being causal [Ellis]
     Full Idea: Spatial, temporal and numerical relations can have various causal roles without themselves being instances of causal powers.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 3)
     A reaction: He cites gaps, aggregates, orientations, approaching and receding, as examples of categorical properties which make a causal difference. I would have thought these could be incorporated in accounts of more basic causal powers.
8. Modes of Existence / B. Properties / 11. Properties as Sets
Properties and relations are discovered, so they can't be mere sets of individuals [Ellis]
     Full Idea: To regard properties as sets of individuals, and relations as sets of ordered individuals, is to make a nonsense of the whole idea of discovering a new property or relationship. Sets are defined or constructed, not discovered.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 2)
     A reaction: This bizarre view of properties (as sets) drives me crazy, until it dawns on you that they are just using the word 'property' in a different way, probably coextensively with 'predicate', in order to make the logic work.
8. Modes of Existence / C. Powers and Dispositions / 2. Powers as Basic
Causal powers can't rest on things which lack causal power [Ellis]
     Full Idea: A causal power can never be dependent on anything that does not have any causal powers.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 3)
     A reaction: Sounds right, though you worry when philosophers make such bold assertions about such extreme generalities. But see Idea 12667. This is, of course, the key argument for saying that causal powers are the bedrock of reality, and of explanation.
8. Modes of Existence / C. Powers and Dispositions / 5. Powers and Properties
Categoricals exist to influence powers. Such as structures, orientations and magnitudes [Ellis, by Williams,NE]
     Full Idea: Ellis allows categoricals alongside powers, …to influence the sort of manifestations produced by powers. He lists structures, arrangements, distances, orientations, and magnitudes.
     From: report of Brian Ellis (The Metaphysics of Scientific Realism [2009]) by Neil E. Williams - The Powers Metaphysics 05.2
     A reaction: I would have thought that all of these could be understood as manifestations of powers. The odd one out is distances, but then space and time are commonly overlooked in every attempt to produce a complete ontology. [also Molnar 2003:164].
8. Modes of Existence / C. Powers and Dispositions / 6. Dispositions / b. Dispositions and powers
Causal powers are a proper subset of the dispositional properties [Ellis]
     Full Idea: The causal powers are just a proper subset of the dispositional properties.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 5)
     A reaction: Sounds wrong. Causal powers have a physical reality, while a disposition sounds as if it can wholly described by a counterfactual claim. It seems better to say that things have dispositions because they have powers.
9. Objects / C. Structure of Objects / 1. Structure of an Object
Categorical properties depend only on the structures they represent [Ellis]
     Full Idea: I would define categorical properties as those whose identities depend only on the kinds of structures they represent.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 3 n8)
     A reaction: Aha. So categorical properties would be much more perspicaciously labelled as 'structural' properties. Why does philosophical terminology make it all more difficult than it needs to be?
9. Objects / D. Essence of Objects / 5. Essence as Kind
A real essence is a kind's distinctive properties [Ellis]
     Full Idea: A distinctive set of intrinsic properties for a given kind is called a 'real essence'.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 3)
     A reaction: Note that he thinks essence is a set of properties (rather than what gives rise to the properties), and that it is kinds (and not individuals) which have real essences, and that one role of the properties is to be 'distinctive' of the kind. Cf. Oderberg.
10. Modality / A. Necessity / 5. Metaphysical Necessity
Metaphysical necessity holds between things in the world and things they make true [Ellis]
     Full Idea: Metaphysical necessitation is the relation that holds between things in the world and the things they make true.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 1)
     A reaction: Not sure about that. It implies that it is sentences that have necessity, and he confirms it by calling it 'a semantic relation'. So there are no necessities if there are no sentences? Not the Brian Ellis we know and love.
10. Modality / C. Sources of Modality / 1. Sources of Necessity
Metaphysical necessities are those depending on the essential nature of things [Ellis]
     Full Idea: A metaphysically necessary proposition is one that is true in virtue of the essential nature of things.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 6)
     A reaction: It take this to be what Kit Fine argues for, though it tracks back to Aristotle. I also take it to be correct, though one might ask whether there are any other metaphysical necessities, ones not depending on essences.
11. Knowledge Aims / A. Knowledge / 4. Belief / a. Beliefs
We can believe a thing without knowing we believe it [Descartes]
     Full Idea: The action of thought by which one believes a thing, being different from that by which one knows that one believes it, they often exist the one without the other.
     From: René Descartes (A Discourse on Method [1637], §3.23)
11. Knowledge Aims / B. Certain Knowledge / 1. Certainty
In morals Descartes accepts the conventional, but rejects it in epistemology [Roochnik on Descartes]
     Full Idea: Descartes' procedure for treating values (accepting normal conventions when faced with uncertainty) is the exact antithesis of that used to attain knowledge.
     From: comment on René Descartes (A Discourse on Method [1637], §3.23) by David Roochnik - The Tragedy of Reason p.73
11. Knowledge Aims / B. Certain Knowledge / 4. The Cogito
In thinking everything else false, my own existence remains totally certain [Descartes]
     Full Idea: While I decided to think that everything was false, it followed necessarily that I who thought thus must be something; the truth 'I think therefore I am' was so certain that the most extravagant scepticism could never shake it.
     From: René Descartes (A Discourse on Method [1637], §4.32)
12. Knowledge Sources / A. A Priori Knowledge / 6. A Priori from Reason
I aim to find the principles and causes of everything, using the seeds within my mind [Descartes]
     Full Idea: I have tried to find in general the principles or first causes of everything which is or which may be in the world, ..without taking them from any other source than from certain seeds of truth which are naturally in our minds.
     From: René Descartes (A Discourse on Method [1637], §6.64)
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Understanding, rather than imagination or senses, gives knowledge [Descartes]
     Full Idea: Neither our imagination nor our senses could ever assure us of anything, if our understanding did not intervene.
     From: René Descartes (A Discourse on Method [1637], §4.37)
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / a. Foundationalism
I was searching for reliable rock under the shifting sand [Descartes]
     Full Idea: My whole plan had for its aim simply to give me assurance, and the rejection of shifting ground and sand in order to find rock or clay.
     From: René Descartes (A Discourse on Method [1637], §3.29)
     A reaction: I take this to be characteristic of an age when religion is being quietly rocked by the revival of ancient scepticism. If he'd settled for fallibilism, our civilization would have gone differently.
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
When rebuilding a house, one needs alternative lodgings [Descartes]
     Full Idea: Before beginning to rebuild the house in which one lives…. one must also provide oneself with some other accommodation in which to be lodge conveniently while the work is going on.
     From: René Descartes (A Discourse on Method [1637], §3.22)
14. Science / A. Basis of Science / 3. Experiment
Only experiments can settle disagreements between rival explanations [Descartes]
     Full Idea: I observe almost no individual effect without immediately knowing that it can be deduced in many different ways, ..and I know of no way to resolve this but by experiments such that the results are different according to different explanations.
     From: René Descartes (A Discourse on Method [1637], §6.65)
14. Science / B. Scientific Theories / 2. Aim of Science
Science aims to explain things, not just describe them [Ellis]
     Full Idea: The primary aim of science is to explain what happens, not just to describe it.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 2)
     A reaction: This I take to be a good motto for scientific essentialism. Any scientist who is happy with anything less than explanation is a mere journeyman, a servant in the kitchens of the great house of science.
15. Nature of Minds / A. Nature of Mind / 7. Animal Minds
Little reason is needed to speak, so animals have no reason at all [Descartes]
     Full Idea: Animals not only have less reason than men, but they have none at all; for we see that very little of it is required in order to be able to speak.
     From: René Descartes (A Discourse on Method [1637], §5.58)
16. Persons / B. Nature of the Self / 3. Self as Non-physical
I am a thinking substance, which doesn't need a place or material support [Descartes]
     Full Idea: I concluded that I was a substance, of which the whole essence or nature consists in thinking, and which, in order to exist, needs no place and depends on no material thing.
     From: René Descartes (A Discourse on Method [1637], §4.33)
     A reaction: To me that sounds like "I concluded that I wasn't a human being", which highlights the bizarre wishful thinking that seems to have gripped the human race for the first few thousand years of its serious thinking.
17. Mind and Body / A. Mind-Body Dualism / 1. Dualism
I can deny my body and the world, but not my own existence [Descartes]
     Full Idea: I could pretend that I had no body, and that there was no world or place that I was in, but I could not, for all that, pretend that I did not exist.
     From: René Descartes (A Discourse on Method [1637], §4.32)
     A reaction: He makes the (in my opinion) appalling blunder of thinking that because he can pretend that he has no body, that therefore he might not have one. I can pretend that gold is an unusual form of cheese. However, "I don't exist" certainly sounds wrong.
Reason is universal in its responses, but a physical machine is constrained by its organs [Descartes]
     Full Idea: Whereas reason is a universal instrument which can serve on any kind of occasion, the organs of a machine need a disposition for each action; so it is impossible to have enough different organs in a machine to respond to all the occurrences of life.
     From: René Descartes (A Discourse on Method [1637], §5.57)
     A reaction: How can Descartes know that reason is 'universal' rather than just 'very extensive'? Is there any information which cannot be encoded in a computer? It doesn't feel as if there any intrinsic restrictions to reason, but note Idea 4688.
17. Mind and Body / A. Mind-Body Dualism / 2. Interactionism
The soul must unite with the body to have appetites and sensations [Descartes]
     Full Idea: It is not sufficient that the reasonable soul should be lodged in the body like a pilot in a ship, unless perhaps to move its limbs, but it needs to be united more closely with the body in order to have sensations and appetites, and so be a true man.
     From: René Descartes (A Discourse on Method [1637], §5.59)
     A reaction: The idea that the pineal gland is the link suggests that Descartes has the 'pilot' view, but this idea shows that he believes in very close and complex interaction between mind and body. But how can a mind 'have' appetites if it has no physical needs?
18. Thought / B. Mechanics of Thought / 6. Artificial Thought / c. Turing Test
A machine could speak in response to physical stimulus, but not hold a conversation [Descartes]
     Full Idea: One may conceive of a machine made so as to emit words, and even emit them in response to a change in its bodily organs, such as being touched, but not to reply to the sense of everything said in its presence, as the most unintelligent men can.
     From: René Descartes (A Discourse on Method [1637], §5.56)
     A reaction: A critique of the Turing Test, written in 1637! You have to admire. Because of the advent of the microprocessor, we can 'conceive' more sophisticated, multi-level machines than Descartes could come up with.
23. Ethics / C. Virtue Theory / 1. Virtue Theory / d. Virtue theory critique
Greeks elevate virtues enormously, but never explain them [Descartes]
     Full Idea: The ancient pagans place virtues on a high plateau and make them appear the most valuable thing in the world, but they do not sufficiently instruct us about how to know them.
     From: René Descartes (A Discourse on Method [1637], §1.8)
26. Natural Theory / B. Natural Kinds / 2. Defining Kinds
There are natural kinds of processes [Ellis]
     Full Idea: There are natural kinds of processes.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 3)
     A reaction: Interesting. I am tempted by the view that processes are the most basic feature of reality, since I think of the mind as a process, and quantum reality seems more like processes than like objects.
26. Natural Theory / B. Natural Kinds / 4. Source of Kinds
Natural kind structures go right down to the bottom level [Ellis]
     Full Idea: Natural kind structures go all the way down to the most basic levels of existence.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 3)
     A reaction: Even the bottom level? Is there anything to explain why the bottom level is a kind, given that all the higher kinds presumably have an explanation?
26. Natural Theory / D. Laws of Nature / 3. Laws and Generalities
Laws of nature are just descriptions of how things are disposed to behave [Ellis]
     Full Idea: The laws of nature must be supposed to be just descriptions of the ways in which things are intrinsically disposed to behave: of how they would behave if they existed as closed and isolated systems.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 3)
     A reaction: I agree with this, and therefore take 'laws of nature' to be eliminable from any plausible ontology (which just contains the things and their behaviour). Ellis tends to defend laws, when he doesn't need to.
26. Natural Theory / D. Laws of Nature / 7. Strictness of Laws
God has established laws throughout nature, and implanted ideas of them within us [Descartes]
     Full Idea: I have noticed certain laws that God has so established in nature, and of which he has implanted such notions in our souls, that …we cannot doubt that they are exactly observed in everything that exists or occurs in the world.
     From: René Descartes (A Discourse on Method [1637], pt 5), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 15.5
     A reaction: This is the view of laws which still seems to be with us (and needs extirpating) - that some outside agency imposes them on nature. I suspect that even Richard Feynman thought of laws like that, because he despised philosophy, and was thus naďve.
27. Natural Reality / A. Classical Physics / 1. Mechanics / c. Forces
I deny forces as entities that intervene in causation, but are not themselves causal [Ellis]
     Full Idea: The classical conception of force is an entity that intervenes between a physical cause and its effect, but is not itself a physical cause. I see no reason to believe in forces of this kind.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 2)
     A reaction: The difference of view between Leibniz and Newton is very illuminating on this one (coming this way soon!). Can you either have forces and drop causation, or have causation and drop forces?
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / a. Energy
Energy is the key multi-valued property, vital to scientific realism [Ellis]
     Full Idea: Perhaps the most important of all multi-valued properties is energy itself. I think a scientific realist must believe that energy exists.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 2)
     A reaction: It's odd that the existence of the most basic thing in physics needs a credo from a certain sort of believer. I have been bothered by notion of 'energy' for fifty years, and am still none the wiser. I'm sure I could be scientific realist without it.
27. Natural Reality / D. Time / 1. Nature of Time / a. Absolute time
Simultaneity can be temporal equidistance from the Big Bang [Ellis]
     Full Idea: Cosmologists have a concept of objective simultaneity, which they take to mean something like 'temporally equidistant from the Big Bang'.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 6)
     A reaction: I find this very appealing, when faced with all the relativity theory that tells me there is no such thing as global simultaneity, a claim which I find deeply counterintuitive, but seems to have the science on its side. Bravo.
27. Natural Reality / D. Time / 3. Parts of Time / e. Present moment
The present is the collapse of the light wavefront from the Big Bang [Ellis]
     Full Idea: The global wavefront that collapses when a light signal from the Big Bang is observed is what most plausibly defines the frontier between past and future.
     From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 6)
     A reaction: I'm not sure I understand this, but it is clearly worth passing on. Of all the deep mysteries, the 'present' time may be the deepest.