Inner tranquility is a goal of the Stoics—mainly so your soul can be calm as you judge the impressions of your mind. The soul is like a bowl of water, the impression like a ray of light that falls on it. When the water is disturbed, the ray of light is distorted. If you judge an impression while your soul is agitated, your judgment cannot be relied on because you are suffering from vertigo. The emotions of grief, pity, and even affection are well-known disturbers of the soul.
