The Other Qualities of our Idea of Space and Time

Time is Sensible Only with Changes

Impressions always precede ideas.

Every idea first appears as a correspondent impression.

However, many of our ideas are so obscure that it is almost impossible for the mind to tell their nature and composition.

Let us apply this principle to discover the nature of our ideas of space and time.

When I open my eyes, I see many visible bodies.

When I close my eyes, I acquire the idea of space, considering the distance between these bodies.

Every idea is derived from some impression exactly similar to it.

The impressions similar to this idea of space, must be:

• some sensations derived from the sight, or
• some internal impressions arising from these sensations.

Our internal impressions are our passions, emotions, desires and aversions.

The idea of space is derived is not derived from these.

Therefore, only the senses can convey this original impression.

What impressions do our senses convey to us?

This question answers the nature of the idea of space.

The table before me is alone enough to give me the idea of space, by its view.

This idea of space is then borrowed from and represents some impression appearing to my senses now.

But my senses only convey the impressions of coloured points, disposed in a certain way.

If the eye can see farther, I want to see it.

But if it is impossible to show anything farther, then the idea of space is just a copy of:

• these coloured points, and
• how the coloured points appear.

Suppose that in this object in space, the points were purple.

Every repetition of that idea, we would:

• place the points in the same order with respect to each other
• bestow a purple colour on them, which is the only color we know.

But after experiencing other colours of green, red, white, black, etc, and finding a resemblance in the disposition of those points, we:

omit the peculiarities of colour, as far as possible, and found an abstract idea merely on how they look. The abstract idea is not hindered from representing touch and sight, because of their resemblance, even when:

the resemblance is carried beyond the sense objects impressions of touch are similar to those of sight in the disposition of their parts. All abstract ideas are really nothing but particular ideas, considered in a certain light.

But being annexed to general terms, they are able to: represent a vast variety of objects, and comprehend objects which are similar or dissimilar in some particulars.

The idea of time is derived from the succession of our:

• perceptions,
• ideas and impressions,
• impressions of reflection, and
• sensations.

This idea of time will afford us an abstract idea, which comprehends a still greater variety than the idea of space.

Yet it is represented in the imagination by some specific individual idea of a determinate quantity and quality.

We receive the idea of space from the disposition of visible and tangible objects.

We create the idea of time from the succession of ideas and impressions.

It is impossible for time alone to ever appear or be noticed by the mind.

A man in a sound sleep, or strongly occupied with a thought, is insensible of time.

The same duration appears longer or shorter to his imagination, according as his perceptions succeed each other with more or less rapidity.

Malezieu has remarked that our perceptions have certain bounds fixed by the mind’s original nature and constitution.

Beyond those bounds, no influence of external objects on the senses can hasten or retard our thought.

If you wheel around a burning coal rapidly, it will present to the senses an image of a circle of fire.

There will seem no interval of time between its revolutions merely because it is impossible for our perceptions to succeed each other as rapidly as the motion of external objects.

Wherever we have no successive perceptions, we have no notion of time, even though there is a real succession in the objects.

From these phenomena, we may conclude that time:

• cannot appear to the mind alone or through a steady unchangeable object, and
• is always discovered through some perceivable succession of changeable objects.

To confirm this, we may add the following perfectly decisive and convincing argument.

Time or duration consists of different parts.

Otherwise, we could not conceive a longer or shorter time.

These parts are not co-existent, because the co-existence of parts:

• belongs to space, and
• distinguishes it from time.

Since time is composed of parts that are not coexistent, an unchangeable object producing only coexistent impressions, produces no impressions that can give us the idea of time.

Consequently, idea of time:

• must be derived from a succession of changeable objects
• in its first appearance, can never be severed from such a succession.

Time, in its first appearance to the mind, is always conjoined with a succession of changeable objects.

Otherwise, we can never notice time.

We now examine whether time can:

• be conceived without us conceiving any succession of objects, and
• alone form a distinct idea in the imagination.

To know whether any objects joined in impression, are inseparable in idea, we only need to consider if they are different from each other, conceived apart.

Everything that is different is distinguishable.

Everything that is distinguishable may be separated.

If they are not different, they are not distinguishable.

If they are not distinguishable, they cannot be separated.

This is precisely the case with respect to time, compared with our successive perceptions.

The idea of time is not derived from a particular impression mixed up with others and distinguishable from them.

It arises altogether from how impressions appear to the mind, without time being one of those impressions.

Five notes played on a flute give us the impression and idea of time.

But time is not a sixth impression which:

• presents itself to the hearing, nor
• the mind finds in itself, by reflection.

These 5 sounds:

• enter the mind,
• excite no emotion in the mind,
• do not produce any affection which can give rise to a new idea.

Emotion is necessary to produce a new idea of reflection.

By revolving over 1,000 times all its ideas of sensation, the mind can never extract from them any new original idea, unless it has a faculty which feels some new original impression from such a contemplation.

But here the mind only notices how the sounds appear.

It may afterwards:

• consider the general sound, without considering these specific sounds, and
• conjoin it with any other objects.

The mind certainly must have the ideas of some objects.

It is impossible for the mind, without these ideas, to ever arrive at any conception of time since time is:

• not a primary distinct impression, and
• nothing but different ideas, impressions, or objects succeeding each other.

Some pretend that the idea of duration is applicable to objects which are perfectly unchangeable.

I take this as the common opinion of philosophers and the vulgar.

To be convinced of its falsehood, we only need to reflect on the conclusion, that the idea of duration:

• is always derived from a succession of changeable objects, and
• can never be conveyed to the mind by anything steadfast and unchangeable.

It inevitably follows, that since the idea of duration cannot be derived from an unchangeable object:

• time can never be applied to that object, and
• anything unchangeable cannot have duration.

Ideas always represent the objects or impressions, from which they are derived.

Ideas can never represent or be applied to any other impressions without a fiction.

We shall consider in Section 5 by what fiction we:

• apply the idea of time, even to what is unchangeable, and
• suppose that duration is a measure of rest and motion.

There is another very decisive argument, which establishes the present doctrine on our ideas of space and time.

It is founded only on that simple principle, that our ideas of them are compounded of parts which are indivisible.

This argument is worth examining.

Let us take one of those simple indivisible ideas which forms the compound idea of space.

Let us separate it from all other ideas and judge its nature and qualities.

The indivisible idea behind the compound idea of space is not the simple idea of space, for the idea of space consists of parts.

According to the supposition, the simple idea of space is perfectly simple and indivisible.

Is it therefore nothing?

That is absolutely impossible.

The real, compound idea of space is composed of no ideas because these many non-entities would make up a real existence, which is absurd.

Therefore, what is our idea of a simple and indivisible point?

My answer will be somewhat new, since the question itself has never been thought of.

We are used to dispute the nature of mathematical points, but seldom the nature of their ideas.

‘Impressions of Atoms’ as Quantum of Space and Time which Have a Quality

The idea of space is conveyed to the mind by sight and touch.

Anything invisible or intangible never appears extended.

That compound impression which represents space, consists of several lesser impressions, that are indivisible to the eye or feeling.

These may be called ‘impressions of atoms’ or corpuscles endowed with colour and solidity.

It is not only requisite, that these atoms should be coloured or tangible for our senses to discover them.

It is also necessary we should preserve the idea of their colour or tangibility to comprehend them by our imagination.

Only the idea of their colour or tangibility can render them conceivable by the mind.

Upon the removal of the ideas of these sensible qualities, they are utterly annihilated to the imagination.

Now such as the parts are, such is the whole.

If a point is not considered as coloured or tangible, it can convey to us no idea.

Consequently, the idea of space which is composed of the ideas of these points, can never possibly exist.

But if the idea of space really can exist, its parts must:

• also exist, and
• be considered as coloured or tangible.

We therefore only have an idea of space when we regard it as an object of our sight or feeling.

The same reasoning will prove that the indivisible moments of time must be filled with some real object or existence, whose succession:

• forms the duration, and
• makes it be conceivable by the mind.