After this we have to understand the idea of the common properties of things; and they refer to cause and effect, notion of reality, and the nature of existence. We have also to understand how we can get the idea of a substance, attribute of a substance, and action, as well as of existence.
Cause and effect: If there be no cause, there can be no effect; but this does not mean that if there be no effect, there is no cause.
Notion of reality: The notion of reality is a fundamental one, for we find that things have a continuous course H of existence. But the characteristics of a substance, attributes of a substance, and action can be universal as well as special.
Existence: That is existence by which a substance, attributes of a substance, and action are said to be what they are. But existence is different from all these; and in spite of its presence in attributes and action, is neither an attribute nor an action.
A Substance: The idea of a substance can be explained by getting hold of a number of substances.
Attributes and actions: In the same manner the nature of attribute and action can be explained by means of a number of attributes and actions.
State of existence: We say that there is a state of existence, because objects that are said to exist possess certain common properties, and do not possess certain other properties, and are characterized by one common state, which is called existence.
Common and special properties of substances: We find that substances have common as well as special properties, and it is necessary to understand them. For instance, the great "elements", Earth, Water, Fire, Air and Ether have such properties, and we should know what they are.
Properties of the "Elements": Earth has properties of form, taste, smell, and touch. Water has form, touch, and taste; Fire has form and touch; and Air has touch. These properties are not seen in Ether.
Special attribute of Fire: We find that a number of things change their form when brought into contact with fire; and this enables us to understand the special attribute of Fire; namely, form.
Character of Air: Touch is the attribute of Air; but it is not the touch of visible things, for Air itself is not visible. It is a substance, but does not possess the state of a substance. It is a substance, because it is characterized by action and attributes; but, as it does not possess the state of a substance, it is sometimes said to be eternal. The expansion of Air is a mark of its variety of forms; but even in a close contact with Air, nothing visible can be seen.
Character of Ether: Going out and going in are the characteristic marks of Ether; and they take place at the same time, because this is not a case of action, but only of contact, for Ether is only in contact with an object.
Sound is an attribute of Ether and of nothing else, neither Air, nor mind, nor the soul.
Ether is a substance like Air, and no more eternal (or non- eternal) than the latter. It is real because we know that it exists; and it exists because we know that sound is its special attribute.
The "elements" have their special properties too. In the same manner we can understand the character of Time, Space, and Sound.
Special attributes of "Elements": Smell is the special attribute of Earth, cold of Water, and heat of Fire.
Character of Time: The character of Time is that it belongs to the future, present, and the past, and is swift. It is a substance like Air, and eternal (or non-eternal) like it. It is real because we know that it exists, and has certain definite characteristics. It is also a factor of action; and things that are not subject to Time are said to be permanent, and those that are, impermanent.
Character of Space: When we describe a thing from a particular point, it is a clear proof of the existence of Space. Space is a substance like Air, and eternal (or non-eternal) like it. It is real because it exists, and has certain definite characteristics, and produces certain effects.
We form an idea of the East because of its permanent connection with the Sun; and it is with reference to that that we have the South, West, and North, and the intermediate spaces between them. There is, however, a possibility of doubt in this.
Sound: Sound is that which "catches" the ears. There are different kinds, of sounds to express different ideas of things. Sound is not a substance, though associated with one; nor is it action, though it has the character of one. It is only a perfect attribute. There is no mark of its permanence, for it is subject to constant change; and it is a mistake to suppose that it can be found in a manifest object.
Sound is produced by means of the meeting and separation of things, and by other sound. The first sound arises from soundlessness. There can be confusion or doubt in a multiplicity of sounds; but generally speaking, it is possible to separate and distinguish between them.