The Mind's Substance

There is no connection between motion or thought just as there appears no connection between all other causes and effects.

Two weights

Place 100 pound weight on one end of a lever and another 100 pound weight on another end. These weights will not move, just as thoughts will not move from seeing this.

You might try to prove a priori that such a position of bodies can never cause thought because it is nothing but a position of bodies. In this case, you must also conclude that it can never produce motion because there is no apparent connection.

You reason too hastily when you conclude that:

• it is impossible that motion can ever produce thought from the mere consideration of the ideas, or
• a different position of parts can create a different passion or reflection.

Because this is contrary to experience.

We might have experienced our mind perceiving a constant conjunction of thought and motion.

Everyone has experienced a change of thought or feeling based on the different positions of their body.

You might then reply that this change of thought or feeling depends on the union of soul and body.

I would answer that we must separate the question into two:

1. The question on the mind’s substance
2. The question on the substance of the cause of its thought

We answer the question on the substance of the cause of its thought by finding out that thought and motion are:

• different from each other, but
• constantly united by experience.

When we apply these ideas to matter, we can conclude that motion is the cause of thought and perception.

Our only dilemma is:

• Dilemma 1a: To assert that an object can only be the cause of another, if the mind can perceive the connection of those objects, or
• Dilemma 1b: To maintain that all objects constantly conjoined are to be regarded as causes and effects.

If we choose Dilemma 1b, then we affirm that there is no such thing as a cause or even the deity himself, because our idea of that supreme Being is derived from impressions.

These impressions would now have no effect, nor any connection with any other existence.

It has been said that the connection between the idea of an infinitely powerful being and the idea of his actions is necessary and unavoidable.

I answer that we have no idea of a being endowed with any power, much less of one endowed with infinite power.

But if we will change expressions, we can only define power by connection.

The idea of an infinitely powerful being is connected with the idea of every effect that he wills. A being, whose will is connected with every effect, is connected with every effect.

But this is an identical proposition. It gives us no insight into the nature of this power or connection.

If the deity were the great and effective principle which supplies the deficiency of all causes, this leads us into the grossest absurdities.

We would:

• have recourse to him in natural operations,
• assert that matter cannot of itself communicate motion, or produce thought because there is no apparent connection between these objects, and
• acknowledge that the deity is the author of all our volitions and perceptions since they have no connection:
  • with one another, or
  • with the substance of the soul.

This agency of the supreme Being has been asserted by several philosophers (Father Malebranche and other Cartesians) with relation to all the mind’s actions, except volition, or rather an inconsiderable part of volition.

This exception is a mere pretext to avoid the dangerous consequences of that doctrine.

If only apparent power is active, then thought would be as inactive as matter.

This inactivity would make us have recourse to a deity since the supreme being is the real cause of all our actions, good and bad.

We are left with Dilemma 1b, that all objects constantly conjoined are only to be regarded as causes and effects.

All objects which are not contrary are susceptible of a constant conjunction. All real objects can be conjoined by the mind.

It follows that anything can be the cause or effect of anything.

This gives the advantage to the materialists.

The question on the soul’s substance is absolutely unintelligible.

All our perceptions do not have to be united with what has space or no space.

Some of them have space, some have no space.

The constant conjunction of objects is the very essence of cause and effect.

Matter and motion may often be regarded as the causes of thought, as far as we know that conjunction.

Philosophers should:

• apologize for their offending conclusions, and
• justify themselves to every art and science, which may be offended at them.

Philosophers such as these are like a king arraigned for high-treason.

There is only one occasion when philosophy will think it necessary and even honourable to justify herself.

That is when religion is offended.

The rights of religion are as dear to philosophy as her own, and are the same.

Therefore, if anyone thinks that my arguments are dangerous to religion, I offer the following apology.

There is no foundation for any conclusion a priori, on the operations or duration of any object of which it is possible for the human mind to form a conception.

Any object may be imagined to:

• become entirely inactive, or
• be annihilated in a moment.

Whatever we can imagine is possible.

This is true whether we imagine:

• matter (a physical compounded substance), or
• spirit (a simple substance that occupies no space).

In both cases:

• the metaphysical arguments for the immortality of the soul are equally inconclusive, and
• the moral arguments and those derived from the analogy of nature are equally strong and convincing.

Therefore, if my philosophy makes no addition to the arguments for religion, it at least takes nothing from them.

Everything remains precisely as before.