premise: The model of consumer behaviour on which neo-classical demand theory is based implies that consumers are perfectly informed about the price and quality characteristics of the products on offer, and are constantly altering their expenditure patterns in response to price and quality changes, so as to maximise their total utility (satisfaction). This model is unrealistic, as the range of products on offer in modern markets is immense, and no consumer has the knowledge or inclination to acquire the information that would be needed to make choices in this way.
hypothesis: Maximising the total utility of a product purchase implies consideration of both price and quality characteristics.