We are still obliged to mount higher, in order to find the cause of this cause, which you had assigned as satisfactory and conclusive.
If Reason (I mean abstract reason, derived from inquiries a priori) be not alike mute with regard to all questions concerning cause and effect, this sentence at least it will venture to pronounce, That a mental world, or universe of ideas, requires a cause as much, as does a material world, or universe of objects; and, if similar in its arrangement, must require a similar cause.

For what is there in this subject, which should occasion a different conclusion or inference?
In an abstract view, they are entirely alike; and no difficulty attends the one supposition, which is not common to both of them.
Again, when we will needs force Experience to pronounce some sentence, even on these subjects which lie beyond her sphere, neither can she perceive any material difference in this particular, between these two kinds of worlds; but finds them to be governed by similar principles, and to depend upon an equal variety of causes in their operations.

We have specimens in miniature of both of them.

Our own mind resembles the one; a vegetable or animal body the other.

Let experience, therefore, judge from these samples.