What is our species' greatest invention? Medicine, computers, space travel? Not even close. The innovation that underlies each of our past achievements and those we still aspire to is language. Language is the ultimate invention of Homo sapiens - one that has allowed us to change the physical and social world around us in every conceivable way, and an invention that has fundamentally changed us, as well.

Noted Japan expert Professor Mark J. Ravina of the University of Texas at Austin covers the politics, economics, and culture of the island nation since World War II - a conflict that saw the end of Japan’s dream of regional conquest, which Professor Ravina calls Empire 1.0. The country’s postwar leaders radically changed course, renouncing a strong military to pursue Empire 2.0 - Japan as an economic colossus.

Railways are one of the most important inventions in modern history. From the 1825 opening of the Stockton and Darlington Railway in England, trains revolutionized both travel and trade and radically changed the way we experience the world. In the 24 richly illustrated lectures of How Railways Transformed the World, you’ll experience the amazing world and impact of railways, from the early 19th century to today’s futuristic trains, including extensive material on the pleasure and appeal of rail travel today.

What is life? What is my place in it? What choices do these questions obligate me to make? More than a half-century after it burst upon the intellectual scene - with roots that extend to the mid-19th century - Existentialism's quest to answer these most fundamental questions of individual responsibility, morality, and personal freedom, life has continued to exert a profound attraction.

Language defines us as a species, placing humans head and shoulders above even the most proficient animal communicators. But it also beguiles us with its endless mysteries, allowing us to ponder why different languages emerged, why there isn't simply a single language, how languages change over time and whether that's good or bad, and how languages die out and become extinct.

Grammar! For many of us, the word triggers memories of finger-wagging schoolteachers, and of wrestling with the ambiguous and complicated rules of using formal language. But what is grammar? In fact, it's the integral basis of how we speak and write. As such, a refined awareness of grammar opens a world of possibilities for both your pleasure in the English language and your skill in using it, in both speech and the written word.

"It doesn't take an Einstein to understand modern physics," says Professor Wolfson at the outset of these 24 lectures on what may be the most important subjects in the universe: relativity and quantum physics. Both have reputations for complexity. But the basic ideas behind them are, in fact, simple and comprehensible by anyone. These dynamic and illuminating lectures begin with a brief overview of theories of physical reality starting with Aristotle and culminating in Newtonian or "classical" physics.

The science fiction genre has become increasingly influential in mainstream popular culture, evolving into one of the most engaging storytelling tools we use to think about technology and consider the shape of the future. Along the way, it has also become one of the major lenses we use to explore important philosophical questions. The origins of science fiction are most often thought to trace to Mary Shelley's novel Frankenstein, a story born from a night of spooky tale-telling by the fireside that explores scientific, moral, and ethical questions that were of great concern in the 19th century - and that continue to resonate today.

In London in the Time of Dickens, you’ll get the unique opportunity to experience the British capital through the eyes of a literary master whose work is inextricably tied to the city and its rich history. Throughout 12 lectures taught by Professor Lillian Nayder of Bates College, you’ll tour the city of London in a time of rapid transformation through the life and work of Charles Dickens, uncovering the history of the metropolis, while also witnessing the everyday experiences of Londoners from all walks of life as Dickens represents them.