We say: the principles from which we proceed when recognizing the state of the brain are the actions of sensation and the actions of reasoning, that is, memory, thinking, imagination, power of imagination, ingenuity; as well as motor actions, that is, the actions of a force that moves organs through muscles; further, it is the quality of the excesses removed from the brain, in relation to composition, color and taste, that is, acridity, saltiness, bitterness or tastelessness, as well as their quantity, that is, their scarcity, abundance or complete retention. This also includes the correspondence, inconsistency or harmfulness of air and food, the large or small size of the head, its good or bad shape, as mentioned in the part about the bones, the heaviness and lightness of the head and how it feels to the touch; quality of sleep and wakefulness, condition of hair in relation to quantity, that is, scarcity and abundance; their roughness or subtlety, their quality, that is, shape - curly or smooth; color - they are black, red or blond; fast or slow graying; constant hair being in a healthy state or loss of health, expressed in the fact that it splits, climbs, falls out, etc. The condition of the neck is also indicative - is it thick or thin, is it healthy, do tumors and mumps often or rarely appear on it - and the condition of the tongue, tonsils and teeth.
The brain can be judged by the state of the forces and actions of the nerve-rich organs associated with the brain, for example, the uterus, stomach and bladder. The conclusion on the organ involved is made in two ways: firstly, from the state of the organ involved with the brain, what happened in the brain is judged; secondly, based on the state of the organ that causes suffering to the brain due to its participation in the disease, it is determined which organ it is, what happens to it, and how the disease spreads to the brain. These signs are sometimes used to judge what the actions and state of the brain are at a given time, or what will happen to it, but has not yet happened. For example, prolonged sadness and gloominess indicate approaching melancholy or the upcoming qutrub; senseless anger portends episodic or hot melancholy and mania, and causeless laughter indicates dementia or stupidity.
We will talk below about how to draw conclusions about various states of the brain based on these characteristics and a detailed explanation of the listed methods in order to reach the end in accordance with the above.
As for the conclusion drawn from the category of actions, actions, if they are normal, contribute to the judgment of the healthy state of the brain, and if they are damaged, then this indicates damage in the brain. Damage to actions, as we have already explained, is threefold: weakness, change, disorder and cessation. Speaking generally about conclusions about actions, it should be said that their weakening and cessation occurs from cold or from the thickness of the pneuma, due to moisture and congestion, but does not arise from heat, unless it increases to such an extent that it weakens the force. As for the disorder of actions related to movement, it sometimes occurs from warmth, and sometimes from dryness.