As for spring, in spring the pulse is balanced in everything and excessive in strength. In summer it is fast, frequent due to the “need for cooling” due to the dissipation of animal strength, due to the dissolution of the pneuma due to the excessive external heat that has taken possession of it, and in winter the pulse is less frequent, slower and weaker, and at the same time small, since animal strength weakens in winter. In some people's bodies, it happens that heat is retained and collected in the depths, and animal strength grows stronger. This happens when the hot nature overcomes the body and resists the cold without succumbing to its action, so that the cold does not penetrate into the depths.
In autumn the pulse is uneven and rather weak. As for the unevenness, the reason for this is the frequent changes in the fall of the side nature, which turns now to hotness, now to coldness, and weakness also comes because of this: the fact is that a constantly changing nature is more harmful than a constantly identical and even one, even if the latter is generally bad. Moreover, autumn is a time contrary to the nature of life, for the heat weakens in the fall and the dryness intensifies.
As for the pulse during the periods between the four seasons, it corresponds to the seasons that surround these intermediate periods.