A distinction is often made between consumption and production goods, or it may be better to say immediate and intermediate goods. Consumption goods are those things which are immediately at the point of gratifying man's desires. Production goods are those things which are not yet ready to gratify desires; some of them, being merely means of securing consumption goods, never will themselves immediately gratify desire. [Sidenote: Value is utility given precision] 3. _Value, in the narrow personal sense, may be defined as the importance attributed to a good by a man._ The vagueness and inexactness of the word "utility," or the word "good," disappears when we reach the word "value." It is not a usual relation or a vague degree of benefit sometimes present and sometimes absent, but it refers to a particular thing, person, time, and condition. Value is in the closest relation with wants, and in this narrow sense depends on the individual's estimate. From the meeting and comparison of the estimates of individuals, arise market values or prices, which are the central object of study in economics. CHAPTER 4 THE NATURE OF DEMAND § I. THE COMPARISON OF GOODS IN MAN'S THOUGHT [Sidenote: Wants and goods must be constantly adjusted] 1. _As wants differ in kind and degree, so goods differ in their power to gratify wants._ This general and simple statement unites the leading thoughts of the two chapters preceding. Confirmation of its truth may be found in observation and experience. The purpose of this chapter is to show how, starting from the general nature of wants and the nature of goods, we can arrive at an explanation of the exchange of goods. Recognizing the simple but fundamental fact stated at the opening of this paragraph, an exchange may be seen to be a rational and a logical result when men are living together in society. [Sidenote: Ripe and unripe goods]