. In that sense there is a need for the past in order to understand and explain the possibility of the present. — JuanZu

Was there always past? Does it mean without past there is no present? Or is it rather without present, there is no past? Was there ever the first present without past in the universe? If there was, where is the first present from?

A good article on Temporal Logic on Wiki.

SEP Article on Temporal Logic by Valentine Goranko.

Now I get to derail threads and be ornery. It's great.

If it is philosophical derailing with good arguments, then fair enough.

What do you mean by "fictitious"? — Corvus

Some words have substantive [referents outside the web of language, some do not. Some do not but pretend they do. Time may be one is them.

When you say "a placeholder", would it be in the form of concept? Or would it be some other form or nature? — Corvus

A kind of concept. An eminently useful mental tool we use to engage with the world. We ideate it as having an essential reality of it's own that we can't clearly articulate. But it does not.

I understand space as physical entity. Do you mean the placeholder could be in space somewhere?
Could it be in the form of property of space or principle of motion? — Corvus

I wouldn't call space an entity, and I don't think you perceive it any more or less than time. When you think you perceive space, you are only perceiving objects and their arrangements. You unify this set of arrangements under the umbrella concept of space. Time may be a similar thing, but with relative motions. We perceive relative motions and imagine an umbrella concept 'time'.

Put another way: What if you abandoned the notions of space and time as metaphysical containers, and thought only of objects and their relative arrangements and motions. What would you thereby lose?

I thought Banno tagged me for chitchat reasons. — fdrake

So did I.

My apologies for compromising you.

Neither space nor time come equipped with intrinsic measurements. Relativity sees to that. Without objects in play there is nothing. There is no independent space were it not for at least two objects. Then there is time, but only if those objects move through space. Space and time are the empty stage, coming alive only with actors therein.

I wouldn't call space an entity, and I don't think you perceive it any more or less than time. When you think you perceive space, you are only perceiving objects and their arrangements. — hypericin

When you pour coffee into a cup, is it cup or space in the cup which holds coffee? If there were no space in the cup, coffee won't be contained in the cup.

Space is also perceptible too. We don't sit on a chair if someone else is already sitting and taking up the space on the chair with her body. We make sure to sit on an empty chair.

We only drive when space is available on the stretch of the road. When space is not available due to the car in front is stationery or road is blocked by work, we stop the car until the road gets cleared and space is available for the car to keep driving.

Likewise even dogs and cats seem to be able to perceive space. They don't try walk through a wall or closed door. They only walk and run when space is available for them.

So, space does things for us (contains and holds), and is perceptible, and also is a precondition for all the objects existing in the universe.

But I see your point. Space is an odd object or entity if we could describe it as entity. I was not sure if it is correct to say space exists. Because it is perceptible, but invisible at the same time.
It exists, if and only if when no physical objects exist in it or on it.

Like time, it seems problematic to say it exists. Space is available. Time passes. But can they exist? In Meinong, only physical beings exist. The abstract beings like time and space absist, rather than exist.

It seems too naive and simple, and even obtuse to say they exist, just because we use them, and can talk about them.

A kind of concept. An eminently useful mental tool we use to engage with the world. We ideate it as having an essential reality of it's own that we can't clearly articulate. But it does not. — hypericin

We are close on our view of time here. My reasoning was telling me that time is a general concept or set which contains (placeholder) for all the temporal objects and events and gives us the tool to describe them.

Hence there is no time in the universe. There are only the objects, space and the movements of objects. — Corvus

Why does the object move? How can it move if there's no dimension of time? The reason we experience time is entropy. As a particle goes from coherence to decoherence it ends up in relation to entropy, forming a direction of energy and movement.

Then, our experience of time is just the resulting motion from entropic forces. Thus, time is a form of motion, of energy dissipating and spreading, of a physical process giving a momentum direction through space.

Why does the object move? — Christoffer

If you drop a stone from the top floor of 10m high building, the stone will fall onto the ground even if no one measured how long it took for the stone to hit the ground. The reason stone fell to the ground was the gravity force pulling the stone from the earth. It has nothing to do with time.

Time only emerges into the equation, because it is measured by someone, and says it took 3 seconds for the stone to hit the ground. But it was totally unnecessary for the movement.

Objects move because of energy or force, not because of time.

If you drop a stone from the top floor of 10m high building... it took 3 seconds for the stone to hit the ground. — Corvus

1.43 seconds, actually.

And it will take that long, measured or not.

Objects move because of energy or force, not because of time. — Corvus

Force is defined as mass times acceleration, and acceleration is change in velocity over time. Energy is force times displacement. So both are inversely proportional to the square of the time taken - less time, more force, more energy.

So you again are exactly wrong.

Put another way: What if you abandoned the notions of space and time as metaphysical containers, and thought only of objects and their relative arrangements and motions. What would you thereby lose? — hypericin

The universe will keep on working as it has been, but human civilization would be much different from now. Once upon a time, long time ago, the cavemen must have lived without language and concepts of time or space.

And it will take that long, measured or not. — Banno

We were talking about why the object move. Not how long it takes to move.
Again, you are talking about wrong things here.

Force is defined as mass times acceleration, and acceleration is change in velocity over time. Energy is force times displacement. So both are inversely proportional to the square of the time taken - less time, more force, more energy.

So you again are exactly wrong. — Banno

Do you even read the posts when you reply to them?

We were talking about why the object move. Not how long it takes to move. — Corvus

You were talking about force and energy, both of which are time dependent:

Objects move because of energy or force, not because of time. — Corvus

Energy and force are defined in terms of time.

You seem to be talking about some high school physics stuff. But here we were talking about why the objects move. Not how long it takes to move.

But here we were talking about why the objects move. — Corvus

Indeed, and your explanation was that they move because of force and energy; yet force and energy are defined in terms of time. Hence, on your own account, they move because of time.

The stuff you claim does not exist.

Indeed, and your explanation was that they move because of force and energy; yet force and energy are defined in terms of time. Hence, on your own account, they move because of time.

The stuff you claim does not exist. — Banno

Are you saying that if you don't measure time, the force and energy doesn't exist?

No.

I'm pointing out that if you have force and energy, then you must thereby also have time.

I'm pointing out that if you have force and energy, then you must thereby also have time. — Banno

But whether you bring in time or not, the object still moves by the force.

I'm pointing out that if you have force and energy, then you must thereby also have time. — Banno

Think this way. Do you mean that before time was invented, the stones never fell from the high cliff down the river?

But whether you bring in time or not, the object still moves by the force. — Corvus

Force and energy are both physical constructs. Time is part of the construction.

Force and energy are both physical constructs. Time is part of the construction. — frank

Please read above.

But whether you bring in time or not, the object still moves by the force. — Corvus

Nothing moves but that a period of time is involved. If it moves in zero time, the force involved would be infinite.

Do you mean that before time was invented, the stones never fell from the high cliff down the river? — Corvus

Not at all. The notion of time being invented is a nonsense.

Force and energy are both physical constructs. Time is part of the construction. — frank

Yes.

Nothing moves but that a period of time is involved. If it moves in zero time, the force is infinite. — Banno

It sounds like a claim of appeal to the equation in high school physics.

Not at all. The notion of "time being invented" is a nonsense. — Banno

Do you claim that time was given down by God to humanity?

Do you claim that time was given down by God to humanity? — Corvus

No.

Only that there is time.

And that claiming that there is force and energy but no time involves a contradiction.

No. — Banno

Where did time come from then?

You want to change the subject? Not surprised.

Where did time come from then? — Corvus

I don't know - indeed, the question may well be useless. We don't need to know where time comes form in order to understand that force and energy involve time. What we might seek is consistency.

Only that there is time. — Banno

That sounds unclear, and meaningless.

And that claiming that there is force and energy but no time involves a contradiction. — Banno

I can push my book here on the desk without knowing anything about time, and it moves. If I measured time it took to move from one side to the other end, I know the time. But otherwise, time is not involved in the movement at all.