Let us for a moment consider the meaning of the word. It has been too much limited in its application to lesions of an osseous nature. Carry the meaning of the word to the extreme. A lesion is any abnormality of the bodily organism. This being true anything which interferes with the normal functioning of the body may be considered a lesion.
Biology teaches that the mainspring of life is in the cell.
Therefore, a certain amount of energy is there resident. Whether it be much or little depends upon its resistance. An agent which we call a stimulus is essential in changing the energy which is latent within the cell itself to that which is active and therefore capable of a certain amount of measurement. Lack of normal structural relation of the component parts of the cell to each other constitutes disease. Dr. Hulett at the Cleveland meeting said that the lesion existed in the cell.