In this use, it has but one signification, and that is, those qualities, powers and faculties which are discovered by experience and observation. Or in other words, when we discover the qualities of a thing, how it acts, and how it is acted upon, we learn its nature.
In regard to all other existences except mind, the only mode of discovering their nature is to ascertain by experience and observation how they invariably appear and act. Thus we decide that it is the nature of water to run down hill by finding that it invariably does so; and that it is the nature of smoke to rise in the atmosphere by observing that it invariably ascends.
Owing to this, mankind often use the word nature as signifying that which is according to ordinary experience. That is to say, the same word is used to express the qualities and powers of things, and also to express that invariable experience by which we learn these qualities and powers. What is according to our ordinary experience we say is according to nature, and what is contrary to ordinary experience is contrary to nature.
Thus it is according to nature for water to run down hill, and it is contrary to nature for it to run up hill.
It is mind, in distinction from matter, which has the power of willing, and this is a power which never is exercised invariably one way or another.
But theologians have practiced this fallacy on themselves [pg 217] and others. They first assume, what is contrary to fact, that mind invariably chooses one way, and that is wrong, from birth to regeneration. This being assumed without proof, they claim that the nature of the human mind is thus proved to be depraved, and totally so.
Having thus, as they imagine, established its depraved voluntary nature, they claim that, like all other things, the mind must act according to its nature, which, being wholly depraved, all its moral acts are consequently depraved.
This is what logicians call arguing in a circle; i.e., they prove that it acts invariably wrong because it is totally depraved, and it is totally depraved because it acts invariably wrong.
But common sense denies the starting assumption; i.e., the invariably wrong volitions of every mind from birth to regeneration. On the contrary, it is claimed that every choice which secures enjoyment without violating law, is right, and that whenever a mind chooses what is right, with the intention to act right, the choice is a truly virtuous act, and that all men make such choices very often before regeneration.
Whatever is according to ordinary experience in the qualities and action of mind, is said to be according to its nature. It is according to the nature of mind, then, sometimes to choose what is good, right and virtuous, and at other times to choose what is evil and wrong, according to its knowledge, temptations and habits. Such a case never was known as a mind that invariably chose wrong.