Intellectual history refers to the history of human thoughts in written form. This history cannot be considered without the knowledge of the men and women who created, discussed, wrote about and in other ways were concerned with ideas. Intellectual history is closely related to the history of philosophy and the history of ideas. Its central premise is that ideas do not develop in isolation from the people who create and use them and that one must study ideas not as abstract propositions but in terms of the culture, lives and historical contexts that produced them. Intellectual history aims to understand ideas from the past by understanding them in context. The term 'context' in the preceding sentence is ambiguous: it can be political, cultural, intellectual and social. One can read a text both in terms of a chronological context (for example, as a contribution to a discipline or tradition as it extended over time) or in terms of a contemporary intellectual moment (for example, as participating in a debate particular to a certain time and place). Both of these acts of contextualization are typical of what intellectual historians do, nor are they exclusive. Generally speaking, intellectual historians seek to place concepts and texts from the past in multiple contexts.
It is important to realize that intellectual history is not just the history of intellectuals. It studies ideas as they are expressed in texts, and as such is different from other forms of cultural history which deal also with visual and other non-verbal forms of evidence. Any written trace from the past can be the object of intellectual history. The concept of the intellectual is relatively recent, and suggests someone professionally concerned with thought. Instead, anyone who has put pen to paper to explore his or her thoughts can be the object of intellectual history. A famous example of an intellectual history of a non-canonical thinker is Carlo Ginzburg's study of a 16th-century Italian miller, Menocchio, in his seminal work The Cheese and the Worms.Although the field emerged from European disciplines of Kulturgeschichte and Geistesgeschichte, the historical study of ideas has engaged not only western intellectual traditions, but others as well including, but not limited to, those in the Far East, Near East and Africa. Increasingly, historians are calling for a global intellectual history that will show the parallels and interrelations in the history of thought of all human societies. Another important trend has been the history of the book and of reading, which has drawn attention to the material aspects of how books were designed, produced, distributed and read.