An assortment:
"The Silent Language" by Edward T. Hall.
Hall was an anthropologist attached to the University of New Mexico. He and his research partner, linguist Norman Trager, were doing research in comparative culture. Hall realized they would need a comprehensive theory of culture to describe what they were comparing and provide ways to compare them. Hall's model was "culture as communication", and the results were presented in the book above. His key point was that most of culture was like the iceberg - 90% of it is processed on an unconscious reflex level. We are no more aware of most of our culture than a fish is of the water it swims in. We only become aware when we are set down in a culture that does things differently than ours. The Silent Language is about how we use space. The followup "The Hidden Dimension looks into how different cultures use time. Many things fell into place when I read Hall.

"Games People Play" by Eric Berne.
Berne was a psychiatrist and founder of the discipline of Transactional Analysis. Games People Play was a PopSci bestseller when first published, which was odd because it's a highly technical volume written for other psychiatrists. His thesis was that most human behavior could be viewed as games, and most of what we did were ways of structuring time. Follow up with his "What Do You Say After You've Said Hello?" and "Beyond Games and Scripts". Hall's work above did much to explain teh behavior of societies. Berne's work does much to explain the behavior of people in societies.

"The Anatomy of Criticism" by Northrop Frye.
Frye was a Professor of English at Toronto University. He had completed a study of William Blake called "Fearful Symmetry", and was attempting to do a study of Spencer's Faery Queen. But he found himself trying to make sense of various terms used in literature, and the result became a work of pure theory, unconnected with any specific works. He refers to poetry and poetics, but his canvas is broader. Part of his problem was that there was no general term in English for a work of prose fiction. It's a set of four essays, covering Historical Criticism, Ethical Criticism, Archetypal Criticism, and Rhetorical Criticism, but makes clear that while each form is valid in its own terms, none fully described literature, and a more synoptic view was required.

"The Structure of Scientific Revolutions" by Thomas S. Kuhn
Kuhn's work challenged the accepted notions of scientific progress, and the notion of steady accumulation. His thesis was that the real progress came from notions that lay outside accepted theories, and provided new paradigms by which reality might be understood, and faced all the resistance transformative ideas face from entrenched doctrine until they are demonstrated to be correct.

"Management: Tasks, Practices, Responsibilities" by Peter F. Drucker.
Drucker was our present generation's primary primary theorist and consultant on the practice of management, and just what management was and what mangers did. This work was probably his magnum opus, where he pulled together the ideas he'd formulated elsewhere into a coherent whole. It's a liberal education not only in management, but in the nature and structure of market based economies.

"The Making of Economic Society" by Robert F. Heilbroner.
This is probably the best single volume overview I'm aware of on economics and economic history, beginning with just what an economy is, and the changing conception of economics through history, with the transition from Traditional through Command to Market economies and the issues involved with each. Many animated discussions I see online about economics make me say "Those words don't mean what you think they do. Please read Heilbroner, and come back when you have. Then we might at least be talking about the same things."

"The Problems of Philosophy" by Bertrand Russell.
Russell is concerned with knowledge, and how we know what we know. He asks "Is there any knowledge in the world so certin that no reasonable man could doubt it?", and concludes that it's one of the most difficult questions that can be asked. When we understand the obstacles in the way of a straightforward and confident answer, we are launched on the study of philosophy, which is concerned with precisely such questions. If philosophy is of interest, this is a superb place to start.

"Religion and the Rise of Capitalism" by R. H. Tawney.
Economies don't exist in vacuums. The are aspects of the societies in which they exist, and reflect the values of those societies. Religion has been a critical part of the value systems of societies for as long as there have been societies, and religious notions on what sort of behavior is acceptable affect the structure of economies by determining what sort of transactions are permissible. Tawney is specifically concerned with religious thought in England affecting social organization and economic issues in the period immediately preceding the Reformation and the two following centuries, but while his focus in England, his description of the way in which Christian religious doctrine changed gradually to make a capitalist economy possible in England, the underlying processes could be applied through Europe in general. Read this as a companion to Max Weber's "The Protestant Ethic and the Spirit of Capitalism", originally written in German and concerned with the Netherlands and Germany.

"Capitalism, Socialism, and Democracy" by Joseph A. Schumpeter.
Schumpeter was an Austrian economist, a contemporary of John Maynard Keynes, and (briefly) Austria's Finance Minister in the 1920's. Like Keynes, he considered himself influenced by Marx. But unlike many others, he believed Marx "asked all the right questions, and got all the wrong answers". Capitalism, Socialism, and Democracy was Schumpeter's (often delightfully snarky) attempt to understand what Marx got wrong and why. It's a useful brainwash after you've spent any time reading MArx or other folks who consider themselves Marxists, and provides a needed sense of perspective.

There's more, but I have to stop somewhere...