Disease is what follows the disturbance of the mind or spiritual matter. When I speak of disease I do not mean to confine the word to any particular phenomenon or disturbance of the mind, but that mind is disturbed like the soil of the earth ready to receive the seed. This disturbance contains no knowledge or thought, any more than a house on fire which disturbs the inmates or spirits, who flee out, not knowing the cause. It embraces mind without truth or error, like weight set in motion without direction. Weight like mind could never set itself in motion, but being set in motion it is called mechanical power. So is mind set in motion spiritual power. Both are governed by laws of truth or error, the fruit shows which of the two powers governs. If it is directed by the wisdom of God no bad results can follow, but if directed by error and ignorance, as ignorance is the enemy to truth, the truth will show which governs. As there is no knowledge in error, it sometimes happens that some results follow, as it did in the case of selling Joseph to the Ishmaelites. They, it is said, meant it for evil, but God meant it for good. Truth does not work in that way (that is, by accident). Truth works by laws, like mathematics; — error like chance.
The answer may come right, or may come wrong (in error) either way it contains no law by which the world is wiser. Ignorance is its life and truth its death. So by error comes disease or death. But by the destruction of error comes the introduction of Truth or Science, or health; and as error is matter or mind, it is the instrument of its own destruction. The matter is not annihilated, but the opinion is.
The combination which shows itself in persons in the form of an opinion, indicates its character by a peculiar show of wisdom superior to its followers, and when disturbed by Wisdom or Truth, it dies, but when not opposed, its opinions are sown into the minds of others, like seed in the ground, which comes forth in some form.
This form which follows the disturbance of the mind the doctors call disease. Here is where all the error lies; they take the effect for the cause. We confound the error and truth together; we take an opinion for a truth. This is an error, for what we know we have no opinion of. Knowledge is the destruction of an opinion or disease. Disease is what follows an opinion, it is made up of mind directed by error, and Truth is the destruction of this opinion.
These ideas, and hundreds of others, have been given to explain the effect of the mind. All admit the mind one thing and disease another. This theory that mind is one thing and disease another, has left the people in darkness, and caused more misery than all other evils put together. It has always been admitted that a theory that cannot be put in practice is not good.
Mind is a spiritual matter which, being agitated, disturbs the spirit. This disturbance contains no knowledge of itself, but produces a chemical change in the fluids of the system. These disturbances may be produced in various ways, for instance, by a shock on the mind, by the death of a friend, or by religious excitement, witchcraft, etc. All of the above contain what is called knowledge, which is communicated to the spirit and sets it to work to form disease, after the form the spirit gives the mind. The mind being the matter under the control of the spirit, is capable of producing any phenomenon.
— Oct. 1859.
P. P. Quimby