Ok i know this is a seriously dumb question. This come from a debate me and my brother had about the rise of western civilization. I ask why is western culture so dominant? My opinions have been formed by the books Guns Germs and Steel and Sapiens by Yuval Noah Harai. I am by no means a history buff and from what i gather u guys probably don't like these books. If ur familiar with these books then u probably already know my arguments for "why white people rule the world" my question is simply, how debated is this topic. My brother argues that western civilization won because white people spread disease and stole all the important innovations from different cultures and this idea is not debated by serious historians. I have a hard time believing this because, as an expert in my field, i know the real nitty gritty stuff is always contended. There always seems to be 2 competing theories for everything. Are there any serious historians that back up the idea that geography played a very important role. Or is this idea laughed at and dismissed. He says for the most part, history is not debated and there is a general consensus on pretty much every topic.
The problem with a discussion like this is that the premises are really poorly conditioned. Of course geography played a big role. The emergence of a settlement above a certain size, for example, depends on arable land and fresh water. Nobody disputes that riverbeds were crucial to most early urban civilizations, or that the steppes favour horseback riders in many regards.
The question is, how far do such geographical explanations go? The rivers of Mesopotamia permitted numerous cities to exist. But you can hardly derive the imperial ideologies of Hammurabi, Aššurbanipal or Darius from geographical features. You can't deduce the coexistence of Akkadian and Sumerian, or Aramaic, Elamite and Persian, as official languages, and the cultural spheres shaped by their usage. You can trace the importance of cattle-herding in Zoroastrianism to its origin in the steppe, but you could hardly predict the confluence of factors that led to its distinct moralism which would shape the policies of the Iranian empires for more than a thousand years.
History ultimately isn't about creating a "scientific model" of the past, but about studying the sources available to us to gain a better understanding of it - and by extension, ourselves and the diversity of mankind.
As for the supposed dominance of the west: it's not really a matter of "stealing innovations", but certainly colonialism played a central role, and the spread of diseases was absolutely important at key points. What historians do is generally to look at the sources from those times, see what happened, and how. The "why:s" tend to emerge mainly as a side product of this process. Sometimes there really is an identifiable sine qua non cause, and sometimes there isn't. The course of historical inquiry is ultimately constrained by the nature and quantity of sources available to us.
The idea that most historical fields are defined by consensus is sheer nonsense; I have to express my doubt that your brother has read deeply in any one field in the strongest possible terms. Perhaps if he's read surface level treatments -'What Happened' in broad terms- he might think there's agreement on that, but no one who appreciates history can think it stops there. We're not just concerned with the what's, but the hows and the whys. Even then, there are plenty of periods of history where the 'what happened' is still very much up for debate.
To touch at least tangentially on your more specific question on the rise of the west angle, one influential theory among many has been what is called the Military Revolution thesis. Its most famous exponents are Michael Roberts and Geoffrey Parker; Clifford Rogers has his own spin on it as well. In broad terms, the idea is that the emergence of gunpowder technology changed the ways wars were fought, and this change in warfare forced states in the 16th and 17th centuries to change their systems of administration and taxation. These effects rippled out into the broader fields of the economy and society, thus giving the states of Western Europe crucial advantages over indigenous peoples around the world.
Other scholars have attacked this theory on several different grounds. Jeremy Black is probably the most focused of the critics, but there are quite a few with their own angles. They criticize the timeframe; these changes take a long time to play themselves out, and it's not for nothing that Parker's book on the subject is subtitled Military Innovation and the Rise of the West: 1500-1800. Some point to later changes, such as increased infantry firepower at the end of the 17th century, while others see medieval developments such as the proliferation of infantry as key.
They can point to significant case studies where the role of gunpowder technology is ambiguous at best; John Lynn's study of the Wars of Louis XIV is a major example, and by and large the British Isles remained aloof from the military developments on the continent, but still became one of the leading world powers. The traditional counter to this last one is generally the argument that while the Military Revolution did not spring up in England organically, it was still imposed from above by William III in the Glorious Revolution.
They criticize the disproportion between cause and effect; Lynn has remarked that big things do not come from small things, and doesn't think new siege engines or fortress designs are so important that they could revolutionize world civilization. More broadly, Black argues that the whole direction of change is wrong; it's not war that shapes society, but society that shapes war. New artillery, fortresses, etc. were an effect of the growing wealth and centralization of European states, not their cause.
The military revolution debate has been at the center of Early Modern military history for decades, and has been called the single most influential concept in the study of Early Modern warfare. This is just one field, but it's an important one, since we attach so much importance to the 'rise of the west' question. I hope this illustrates the debates within debates you have in history, where individual arguments about a single question -why did the West(TM) Rise(TM)- have their own divisions.