Cause and Effect

The natural light shows that the total cause of something must contain at least as much reality as does the effect.

Two things follow from this:

1. Something cannot arise from nothing
2. The more perfect is something that in itself has more reality. This cannot come from the less perfect.

This is plainly true for:

• ‘actual’ or ‘intrinsic’ reality, and
• the representative reality of ideas

This representative reality is the reality that an idea represents. A stone, for example, can only exist if its effects match their causes in the stone.

Similarly, heat cannot be produced in a cold object that has no heat.

The idea of heat or of a stone can be caused in me only by something that contains at least as much reality as I conceive to be in the heat or in the stone.

For although this cause does not transfer any of its actual or intrinsic reality to my idea, it still cannot be less real.

The only reality needed by an idea is that which comes from my thought, of which it is a mode.

Any idea that has representative reality comes from a cause that has as much intrinsic reality as there is in its representative idea. If an idea has something that was not in its cause, then it must have gotten it from nothing.

But the reality in something’s being represented in the mind by an idea certainly is not nothing. This is because something cannot come from nothing.

The Cause is Not an Idea

The reality in my ideas is merely representative. Some might think that it is connected to its cause only representatively and not intrinsically. That would mean that the cause is itself an idea.

But that would be wrong.

Although one idea might originate from another, there cannot be an infinite regress of such ideas. Eventually, one must come back to an idea whose cause is not an idea. This cause must be a kind of archetype containing intrinsically all the reality or perfection that the idea contains only representatively.

So the natural light makes it clear that my ideas are like pictures of real things. These pictures can easily fall short of the perfection of those things and can never exceed them.

This reasoning proves that I am not alone in the world. This is because my ideas are mere representatives of a reality which is outside of me, caused by Something else.