Abstraction does not mean that what ever it describes can be ignored or does not exist.

Let me try again.
To 'abstract' means 'to take out from', from the Latin word meaning 'to drag away.
What we abstract, we keep, we notice, we study. What remains is irrelevant, we are indifferent to it, we ignore it.

Precis, condensation, gisting, review: all are means of taking and showing the important bits to someone.  If I read a condensed book, I almost never feel the need to find out what words were left out.  I am happy to forever remain ignorant of it, and to joyfully continue breaking the pedagogic rules of grammar.

So with mathematics.  Imagine a professor trying to teach somebody who keeps writing, e.g. -0.75 evey time the professor asks them to write down 0.25 - my point being that every concept has been 'dragged away' from a real thing or another concept.  In my example, a quarter can only be understood by its implicature - the other three quarters that came with it from the original conceptual whole.

Try to imagine this with the eyes of a child.  A parent is trying to teach numbers.  There are four toys in the box, the parent takes out one and asks "How many toys in the box?"  In order to answer the question with accuracy, the child must completely ignore the toy that is not in the box.

It is this that I mean when I talk about ignoring things.  It's flip side is focus.  If I say that mathematicians ignore a lot of things, then I am only saying that they are highly focused people.  But we all are.  It's in our neural mechanisms - but I shall deal with that in another part of this saga. 

Our notion of time is abstracted from our ideas of space - itself a dubious abstraction from other notions - in the linguistic-cognitive sense.  People who think about time note that we can only go forwards, never backwards or sideways, upwards or downwards.  In exactly the same way that we can never truly grasp the concept of a four-legged tripod, we can never truly grasp the idea of these motions in time.  Our grasp of the tripod concept, being well ingrained, prevents us from even truly thinking about a four-legged variety.  In exactly the same way, we cannot grasp the possibility of going backwards in time.

Forget about the laws of thermodynamics, for now, I'm talking about the way our brain censors its own thoughts.  Just as it is unthinkable to go sideways or vertically in time, so it is unthinkable for so many people that time has no real existence.  The model-in-the-brain works perhaps too well.  Try to imagine building a humanoid robot.  You could implant any reality you wish.  Stick in Isaac Asimovs three laws of robotics and, for the robot, it will be quite literally unthinkable that arobot might harm a human.  On being told that it had, in fact, harmed a human, it could only refuse to accept that as a meaningful statement.  A bit like a biologist arguing with a creationist?

Hmm. This reply is growing into an essay.  Best stop there.

Your turn at bat.

It seems clear to me that animals have memory, which suggests that they
recollect information from the past.  However, it is even more telling
that negative experiences can be recalled and projected to the future,
which indicates that an animal can relate past events to future
consequences.

Agreed.  But almost all neural events follow this pattern.  It is purely mechanistic - a stored value is compared with an input.  The fact of storing a value for purposes of comparison cannot be taken as any proof of time as a reality.  Computers can compare stored values with fresh input.  Computers also have clocks, but that is an anthropocentric word for a particular type of 'gadget'. 

At a guess, about half of all words are anthropocentric.  Describe a fire as cosy or fierce and you are ascribing anthropic properties to fire.  We ascribe anthropic properties to time and space all the time.  Time passes us by.  Us - anthropic through and through.  We waste time.  Nature has no waste, the notion is as anthropic as 'suvival of the fittest'.  Everything we think we 'know' about time can be analysed down to anthropic principles.

The fact that the Earth rotates affects all of life, and even the geology of the planet.  Other life-forms are affected by this rotation, but it takes human insight to invent a concept, apply a label and call it a cyclical phenomenon.  Ice formation, CO2 formation, these too are cyclical.

Suppose an alien intelligence to have formed in an environment where everything is more truly cyclical than on Earth - a place where there is quite literally a time for every purpose under the alien's sun.  Such an intelligence might be cognitively incapable of even thinking about our linear time concept.  Time is an idealisation, a cognitive construct.  It has only as much physical reality about it as does a thought.

Your turn.  :)

A occurs before B and as a consequence it results in a particular outcome.

Before is a spatial notion. It means 'in front of', and was formerly used in that sense frequently in common speech.  In modern English we still use phrases such as, when driving: "It's just before the post offics."  But the sense of time that we were taught as children grabs hold of 'before' and stuffs it into our time paradigm.  Look at a map.  Where did the 'before' vanish to when translated from a 3-dimensional world onto a 2-dimensional map?  When using a map, we tend to refer to the 'sides' of things.  Time doesn't have sides.  How come, in going from a 3-d model to a 2-d model we actually gained an extra dimension that allows e.g. sides of town?

mathematics has the commutative property which indicates that for certain operations, order doesn't matter.

Agreed.  An example where it does matter is cryptology.  In a conventional process on a data stream all encryptions must be used in a last-on first-off sequence.  But commutative encryption is possible if you apply a different paradigm.

requiring an interval for information transfer.

That lies at the heart of my theory - what is the cause of the thing we call 'delay' which goes right to the heart of our intuitions about time?  I will cover that as the core material.

differential equations work by examining the incremental change over time, so real or not, it becomes a necessary device to quantify those changes between intervals.

I would say sufficient, but not necessary.  Other methods are possible. Any one of them might prove sufficient.  Solving the n-body problem requires sufficient and necessary components in a function such that any computational errors are trivial in cosmic timescales. Instead of time-slicing you can space-slice.  Instead of plotting planetary motions at incremental times, you could, perhaps, plot velocities at incremental locations, based on dealing with the objects in a logical sequence, as arrays of data (mass, vectors) in a computer program.  Although it is possible to think of such a program as time-slicing the problem, that's just an emergent property of a system controlled by an oscillator.  With the right hardware you could parallel-process the whole n-body problem with n processing cores in parallel, using Boolean logic.

theoretical physics. The latter has evolved tremendously after the
development of language. So abstraction means something else in
mathematics and physics.

Language is an example of evolution in progress.  It is developing even as I write this.  Democratically, even.  In an evolutionary parallel, language has its deleterious components.  For example, use of the phrase 'the exception that proves the rule' is not conducive to the understanding of science.  It used to be, when 'prove' meant 'test rigourously'.  But the best evolutionary parallel is when two vocabularies merge without their grammars.  The result is a 'creole'.

Linguistics, in the wide sense in which I use it here, encompasses observations in information theory, communications theory, cognitive theories and, yes, physics.  In fact, since all disciplines must use language, the investigation of the grammar and vocabulary of a discipline is most insightful.  Some of the useages are quite elegant, in the mathematical sense of that term.

Every discipline tries hard to compartmentalise words in order to use them as precision tools.  But the public carries on regardless.  The current problem with the theory-as-meticulously-crafted model vs theory-as-a-top-of-the-head-idea model is an example.  Perhaps we should start saying 'theorem' again?

All languages have terms for the vectors of locations in space, and motions in space, in both cases observer-relative and reference object-relative.  Even third-party-relative is possible. In many languages, such as English, we also have a pretty good range of reference-object viewpoint-relative terms.  'In front of' the book is not the same as 'the front' of the book, and can mean a location in the space outside of the book, or inside the book.

We only have a notion of three spatial dimensions and we cannot think 'nothing'.

I have no problem in imagining a tesseract.  Similarly, most people have no problem imagining 'nothing'.  The arabs even invented a symbol for it.  Zero is a universal symbol for 2 - 2 or whatever.  It can be explained.  It is a bucketful of something when you take that something away, but without the bucket.  It is an infinite cosmos sans matter sans energy, sans everything. 

My problem with the space-time hypothesis is this:  our notions of space and time can be shown to derive within our brains  directly from highly filtered information about matter and energy and nothing else.  It's not linguistics, its physics.

Math is a wonderful tool.  Without math we could never know about the massive electromagnetic spectrum that lies entirely outside of the miniscule portion that affects us directly.  Math predicted Neptune, Pluto, Helium, nuclear fission and fusion and the very binary computer that I am using to write this.

Pragmatic philosophy defines truth as whatever works for us, or 'if it ain't broke, don't fix it'.  Math works for us.  It is the most powerful tool we have.  My argument is merely that math can make a plethora of different models.  We can choose to think of space in the Euclidian abstraction of three dimension.  Or less.  Or more - four is nothing, why not a busy-beaver-number of higher dimensions?

A model is only as good as the productive answers it provides.  In everyday life, 3-d space + time ain't broke, so I'm not aiming to fix it.  What I am aiming for, what I am aiming to prove is the grand illusion of time.  I am going to show, in part two, how all clocks, without exception have just one common, non-trivial factor, and it isn't the counting of seconds, or any other unit.

I hope to have part two polished up for publication very soon.  Thank you again for your input - it really is most helpful in showing me the points I need to clarify in the next parts.  I love scientific debate.  It's like a friendly discussion in a bar, but without the bruises.  :)

English is not my mother tongue so I lack somewhat in expressing myself clearly

I had a strong impression that English was your first language - your command of English is a lot better than many English-born people I have met.  I am absolutely serious.

Let me try the 'abstract' thing again.  Please treat it as a special use of the term in philosophy.

An example.  It is a demonstrable fact that you have to teach people the concepts of left and right by some sort of physical demonstration.  That observation was first made, if memory serves, by Carl Sagan.  If ever we made contact by radio or whatever with aliens, we could never express to them exactly how to differentiate left and right.  The assignment of these two words is completely arbitrary and mutually dependent.  Left and right have no demonstrable, universal  real existence.

All relative terms which derive from, or point to, 'leftness' or 'rightness' are likewise arbitrary and not physically or mathematically derivable from real entities.  So:  left, right, clockwise, anticlockwise, north south, east, west; all are arbitrary abstractions from our prior ( not a priori) notions of space.  Where, then is the north pole?  The real one?  The north pole doesn't have any real existence, but despite that, people find nothing strange in going there.

How can anyone possibly go to a place that has no real existence?  The answer to this paradox is the same as the answer to Zeno of Alea's paradox regarding the tortoise and Achilles.  We are natural born pragmatists.  We deal with Achilles and the tortoise as if Zeno's math is all wrong, without needing to know why it's all wrong.  Logic, i.e. our human, in-the-brain pragmatic logic says: "That is too silly to even think about."  And so, explorers and scientists will continue to visit the north pole, even if they agree with my formal logic.  Their pragmatic logic says to travel in a certain manner and to reach a certain goal "as if" there really is a north, and yes, a north pole.

Fridtjof Nansen  had a way with words.  I would have loved to read his description in scientific poetry of what it is like to stand on a mathematical abstraction where east and west vanish as if they never existed  (which they didn't) and where all paths lead only south.

By similar reasoning, much of what we strongly feel to be 'just common sense' can be shown to be built on mental abstractions dating back perhaps before language itself.  Take any of our current notions about the cosmos.  If it can be directly weighed, measured or felt through the senses or instruments* then it might be said to be real.  Gravity, for example.   Oh yes, Volts.  I can refuse to believe in electrons if I wish, but that will never prevent them killing me if I'm careless.  Not so with time. 

If an idea can only be traced back to such primitive mental constructs as the core abstractions of the mind, then we have no proof of its reality.  Our neural system of sensors and brain is a proven liar.  What it can't see doesn't exist.  So, that would be infra-red radiation then - and a whole lot of other demonstrables.  * A clock doesn't count, we cannot show the thing that it is believed to be measuring - why does science  give the  time belief system house room?  Clocks measure time, and time is what clocks measure.  Well, most clocks that we are familiar with do tend to be somewhat circular.

We know about the cosmos we inhabit by comparing like with like.  We can measure one wavelength, or frequency, against another, so the whole electromagnetic frequency is real.  We can measure microscopic fluctuations in pressure waves, so sound is real.  Mass? No problem.  Energy? No problem.  Time? 
Yes problem.  It is what physics continues to call 'the problem of time'.  Does it even exist, or are we using it in an abstract as if  sense, just like those polar explorers?

And that is what I seek to address - as a scientific theory for discussion, debate, demolition even.  Just so long as human knowledge advances one iota I will be happy to have contributed to that.

The issue of Achilles and the tortoise was dealt with by indicating that the infinities involved are simply abstractions of the mind (stated by Aristotle).  This is a well-known outcome of the seeming paradox.   Similarly concepts like "left" and "right" are easily demonstrable by they exist by convention and not as independent facts (being a result of bilateral symmetry).

I would also suggest that you may think you can imagine nothing, but your use of the word infinite already introduces a problem, since, the universe is no such thing.  It is already an abstraction to refer to something as infinite (since it only exists in the mind).  In other words there is no "real world" manifestation of anything that could be called infinite.

In mathematics the objective is to be logically consistent and independent of linguistic idiosyncracies.  The concept of 2 + 2, isn't simply dropping an object's name, but it is contingent on developing a theory of counting, the legitimacy of adding 1 to derive the next number in a sequence, and ultimately the validity of adding two such values together to predict a third.  In short 2 + 2 is a complete abstraction and relates to nothing until we choose it to represent a particular set of objects.  Then we have ported the abstraction of mathematics into the real world and find that it is useful and works for us.

In fact, quantum physics specifically ignores the interpretation of language in evaluating the physical phenomenon that represents reality.  In this case, the mathematics is the only way to demonstrate what is "real" and language is limited precisely because of its origins in our experience only.

This would lead me to conclude that time is meaningful only when
detectable changes occur in the universe and that it represents a means
of consistently marking out the frequency of those changes.

You have a solid core of observable data there:  detectable changes.   And a clock is but a means to correlate those changes according to the known laws of physics as if time really existed.  But the as if is just a useful pragmatic tool, in my submission.

Yes, there are virtually infinite changes going on in the cosmos.  We have no law of physics to say why these changes aren't going on in the reverse sense.  What essential component of the cosmos prevents all possible changes from being reversible?  Why is it that the proverbial 'all the king's horses and all the king's men' -  a metaphor for powerful forces  - can't cause an egg to be 'unsmashed'.

I won't be long, I hope, with part 2.  That will be a short history of clocks - horology if you like. 
I suggest that the first hint of a sense of time predates language.  There are many natural phenomena that rather neatly slice up the day/night cycle.  From an anthropocentric viewpoint there are more for the day than the night.  A single example: the dawn chorus.  (I think most city dwellers will never have heard this.)

Our 'biological clock' doesn't give us an intuitive sense of time, and wasn't discovered until long after the invention of clocks.  It is called a clock only by simple analogy.  It's a rhythm controller -  like the 'clock' in a digital device like the computer, or like the conductor of an orchestra.

The notion of time as something 'real', and the notion of time as something we measure, are two sides of the same coin.  It is impossible to measure 'nothing', so what is it that clocks measure if not time?  I'll make a suggestion in part 2 and elaborate in part 3. 

Meanwhile, it is way past my bed 'time', so I'll bid you a very good night.

to be continued ...

I also think that in some ways we're agreeing that time does not actually have a separate physical existence beyond the word that we use to describe the interval between events.  This is why I'm indicating that it is useful, since I'm not suggesting that that is a sufficient reason to declare it a "real" phenomenon.

While time may not be intuitive, it is clear that the human brain is quite adept at recognizing patterns, so it isn't much to imagine that when humans experienced cyclical events (i.e. day/night, seasons, etc.) they realized that it might be handy to be able to predict when such events would recur.  This undoubtedly lead to the astronomical observations that helped them to recognize that events would occur when a particular constellation was seen in the sky (indicating seasonal changes).  After a time, this would have become formalized to be more independent of external events and lead to the creation of a calendar. 

I would agree that the sense of time is learned, just as our concept of counting.  These are learned elements that are not intuitive but reflect our use of abstractions to make sense of the world.  In effect, it could be argued that these abstractions are simply our mental models of the universe and can't accurately reflect reality, but nevertheless give us the necessary parameters to formalize our understanding of the universe's operation.

To return to my example of music, the concept of timing in music is a similar abstraction to simply provide a structure against which notes are played.  In fact, there are some songs that stretch the boundaries of our "tolerance" to manipulating timings, but they never become chaotic which would render them unstructured and not in line with our view of what music should be.  In no way am I suggesting that this makes time a real independent entity, but rather that it, once again, simply marks our progress from one event to another.

Just like in mathematics, we can almost consider our "sense of time" to be axiomatic and not derivable from simpler principles.

I'm assuming that you didn't mean "magificently", however your use of "form" instead of "from" looks like it could be deliberate.

"what aspect of time makes it appear to be a container?"

If time is simply a "counter" of intervals between events, then we perceive an opportunity to "fill" each interval with more events (and therefore maximize our use of time).  Similarly when we don't do anything, we view it was "wasting" time.  We can't control it, because it is the basic "heartbeat" of the universe itself.   Therefore as the universe continues it's entropic march, time continues unimpeded.

It is interesting to note that the one point where we experience no time is when we sleep or dream.  In that case we are operating in a completely self-contained mental state and not taking account of external events in the way we normally would when conscious. 

I also think that one of the reasons why time has become so important to us is that it is the basis by which predictions are made.  Science unequivocally requires the concept of time to make predictions of how phenomenon are expected to behave in the "future".  Similarly since our brains provide a vehicle for operating in a completely internal fashion (i.e. ability to construct stories and fantasies).  The concept of time becomes an important ingredient for our ability to plan a "future" action and anticipate how events will unfold in some future time.

I suspect that animals similarly have a rudmentary sense of time, just like they do with counting, but it is simplistic and not refined to serve except in the short term (I know, small time interval).  In the end it comes down to the fact that events occur in a certain order and (by inductive reasoning), they have never been observed to occur otherwise.  Therefore by marking the beats, we have a means by which we can assess changes and predict future outcomes.

I don't think it's fair to say it is anthropocentric because the concept of change is intrinsic in the universe itself, although it is uniquely human to have a means by which we mark such change.  I think that this mechanism is also closely tied to our mathematical views in suggesting the concepts of "first" and "last".  Since we can perform such operations on any numbered set, it is a logical extension to include events as another set that can be counted and measured.

From this perspective your idea of using sounds to create a relationship between the abstraction and the recognition of the sound representing the object or event.  From this point, it seems that a
workable language could've evolved rather quickly.


It is interesting to note that language doesn't actually do much good during an actual hunt, so it's primary value would come from being able to plan or anticipate an action in the future.  This is where I can see the need for language to express the abstractions as well as how time would've become more intuitive since all such "conversations" would have invariably involved future events.

Here, you are not just echoing my own thoughts but adding an underscore and a harmony.
You could have a whole new career in linguistics.  :)

a workable language could've evolved rather quickly.

The 'language spurt' is observable as part of a child's language acquisition:article
The 'language spurt' in evolution is a current topic of debate:free pdf

all such "conversations" would have invariably involved future events.

And that, my friend, addresses the correct question, to paraphrase a character in the movie 'I,Robot."
Planning a strategy implies a pragmatic acceptance of the general predictability of nature.

 "That religion developed in man is no accident."

I think it may well have been an accident (or sorts anyway).  A fundamental problem to all humans is how knowledge is conveyed to future generations.  If we go back to more primitive times, we can eliminate all the current methods of recording knowledge and get back to first principles.

To improve the chances of survival it becomes critical to convey as much information as possible to offspring that may be too young to have the necessary analytical capability to process it.  Therefore, it is easiest to convey complex ideas in the form of a story, as a sort of mnemonic device. 

This is why one of the common themes that we see in all religious systems is the wide range of stories that are all intended to convey some lesson or idea.   A story is often more effective to get the point across because the nature of the process precludes analysis and tends to operate at an almost emotional level.

Using this vehicle it isn't hard to see that the more important the story is, the more "authority" it needs to possess if it is to have any long-term power.  Embellishing stories to go beyond teaching lessons to explaining origins and the role of people would serve as a cohesive bond for any group.  This common mythology would be the unifying force that blends the stories and the history of a people together.  From here, it is virtually guaranteed that it becomes religion whether or not a divine being is introduced.  This would also be the basis for the oral traditions we normally associate with any society.

It is also important to consider that in times of stress we are unusually prone to looking for help or seeking assistance for any quarter.  Coincidences or anything that makes us feel better (or better able to cope with circumstances) would be a powerful force in our existence.  I don't think it's any coincidence that the modern day equivalent is the individual that "finds" Jesus after a term in prison.

Remind me never to write about quantum entanglement. I do not think I would like being cursed by Gerhard, someone far more insightful and intelligent than I am.

This has given rise to Adam's Uncertainty Principle which states simply:

"I am uncertain about virtually everything I thought I knew"

Regarding the child's perception of time, my own personal "theory" is that it may be linked to one's longevity.  In other words a month to a 5 year old represents 1/60 of their life, while to a 50 year old, it would represent 1/600th of their life. 

In other words, as we live longer, each unit of time becomes a smaller and smaller part of our total "time experience" that it appears to move faster since we have a longer sense of time with which to compare it.

I've also found a curious correlation to the idea that the more events we engage in, the slower time seems to go, whereas when we have little to distinguish an interval, it seems to go faster.  Once again, I suspect that the more we have happening during any given interval, the more it seems we've accomplished so it satisfies our sense that "time was not wasted".  Therefore it seems that it moved "slower".

Bear in mind that the last example, specifically relates to our interpretation in hindsight, so it doesn't necessary reflect our perspective when it's happening.

Regarding the first part of your question:

If time is simply a "notion" of how we experience changes in events, it doesn't necessarily mean that it has an actual existence (i.e. a property of reality or the universe).  It simply means that from our brain's perspective we are seeing a cause-effect relationship that seems to be consistence in how we experience the world.  Therefore since this is simply our own internal perception, we can derive any means by which we can create "change" and use that as a measure against other events. 

When I say "create change", I mean that it is our invention of clocks which by a system of oscillations or gears (or whatever) provides a consistently rhythmic set of changes which we use to represent our view of how time flows.  So even when we perceive nothing changing, the clock itself is to let us see how an interval as elapsed.

You can see the problem here, is that the only units of measure we have are those that WE have specifically derived, so it is hard to disassociate time as a unit of measure and as a "notion".

When we get into something like relativity where we can experience "time dilation" (time slowing down), we have to answer the question of is time actually different or is it simply our measurement of it?  The point is that our reference frame determines how we interpret clocks in another reference frame, so the implication is that time itself is unaffected, but only our measurement of it between different reference frames is involved.

Once again, we haven't actually established a separate existence for time as an actual property of the universe, but only of our ideas of simultaneity and measurement.

In a nutshell, consider how time could be measured without a clock?  What if there were no time signatures in music?  What would the concept of time mean if there were no changes (and no clocks)? 

Note that in the last question, this would have to be independent of an observer, since the observer's body itself would contain rhythms that promote measurement.

Gerhard:  The curse worked.  :)

I am sitting here at the tail end of my third migraine this week, with a high temperature.

Everybody:  thank you all for your inputs.  I've read the comments posted since my last login.  I'll respond later, over in  part 2.

Let’s find more data though, and more experiments, and as if all science not be married to our old ideas.

Matthew: thank you for your comment.  I am grateful for all feedback.

Much of science is, in a non-obvious way, married to old ideas.

In my approach I am trying to re-evaluate these old assumptions.  Our current cosmological theories can be traced back to a foundation in Newtonian-Euclidian mechanics.  If that foundation is, or can be, or needs to be re-evaluated, then our current building will be on a more sure and lasting foundation.

Not knowing how to run.

Heck, the centipede had it easy, we humans don't even know how to walk!

Just try walking whilst focusing intensely on your own act of walking. 
Now, doesn't it feel all strange and wobbly?

Thinking about walking, during the act of walking, makes walking difficult.
I conclude, therefore, that some thoughts are best left unthunk.

Mark: thank you for your comment.

My point in writing this intermittent, and still ongoing, series about time is to try to show that time has no reality greater then our abstractions from memory and goal-seeking.

I particularly  like your observations about our knowledge of death.  It may well be that our perception of a pressing need to 'get things done' before we inevitably 'move on' has led us to grant a greater 'realism' to time than it warrants.

Time is one of the two biggest unknowns in our understanding of the cosmos - the other being gravity.  I am convinced that we will never understand gravity until we accept that time has no real physical basis.  On the other hand, time's counterpart, inertia, has I believe a very real physical existence and is an area of study much neglected in physics.

Gerhard: when I finish my short series on the history of English, I'm planning to tie up some loose ends and continue this theory of time discussion.  The Allais effect was giving me problems, but I now think it is a purely gravitational non-anomalous effect explainable within Newtonian mechanics.  It's nothing to do with time, but is of relevance to the concepts of constancy and information.

Human perception of time is mainly a problem in linguistics.  We grasp all other concepts by direct experience or by example.  In the case of time, the only 'direct experience' isn't direct and it isn't experience.  Memory and prediction, or interpolation and extrapolation?  Either way, the only thing which we can grasp and attribute to a flow of time is an imperfect model of a flow of information, but it is not direct experience.

Human experience, whether as memory or writings, is like tree rings and rock layers.  It is just another means whereby observers can match data points so as to agree on a more extended history than can be recorded by any one person.  By treating history as a line, we feel that it has a reality and a dimension.  But a physics without time is a physics that makes a lot more sense.