Bava Kamma 2A

מתני׳ ארבעה אבות נזיקין: השור, והבור, והמבעה, וההבער.

Mishnah: There are 4 primary categories of damage: The category of Ox; and the category of Pit; and the category of Maveh, which, based on a discussion in the Talmud refers either to the tooth of an animal that causes damage or to a person who causes damage; and the category of Fire.

לא הרי השור כהרי המבעה, ולא הרי המבעה כהרי השור; ולא זה וזה שיש בהן רוח חיים, כהרי האש שאין בו רוח חיים;

Each of these categories is unique; therefore, the halakhot of one cannot be derived from another. The defining characteristic of the primary category of Ox is not similar to the defining characteristic of the primary category of Maveh, and the defining characteristic of the primary category of Maveh is not similar to the defining characteristic of the primary category of Ox. And the defining characteristics of this category of Ox and that category of Maveh, in which there is a living spirit that causes damage, are not similar to the defining characteristic of the category of Fire, in which there is no living spirit.

ולא זה וזה שדרכן לילך ולהזיק, כהרי הבור שאין דרכו לילך ולהזיק.

The Mishnah continues: And the defining characteristics of this primary category of Ox and Maveh and that primary category of Fire, in which the typical manner of their components is to proceed from one place to another and cause damage, are not similar to the defining characteristic of the primary category of Pit, in which the typical manner of its components is not to proceed from one place to another and cause damage; rather, it remains in place and the damage is caused by the injured party proceeding and encountering the obstacle.

הצד השוה שבהן ⁠– שדרכן להזיק, ושמירתן עליך; וכשהזיק ⁠– חב המזיק לשלם תשלומי נזק, במיטב הארץ.

The common denominator of the components in all of these primary categories is that it is their typical manner to cause damage, and the responsibility for their safeguarding to prevent them from causing damage is incumbent upon you, the owner of the animal or generator of the fire or the pit. And when a component of any of these categories causes damage, the owner or generator of the component that caused the damage is obligated to pay restitution for damage with best-quality land.