It's a simple question. I believe that your language will determine whether or not you develop above average intelligence. I think that without language humanity wouldn't have built any of the scientific devices they now possess.
Huh? Without language humanity would never have emerged from the Mesolithic Era. The planning, organization, and passing of knowledge from one generation to another that marked the transition to the Neolithic Era with its agriculture and permanent settlements would have been impossible without language. It's been recently hypothesized that language was first invented before we left Africa. It's possible that language is the technology that made possible the diaspora of Homo sapiens in the first place, that without it we could not have successfully migrated into Asia Minor, where we invented civilization and all of those scientific devices.
Furthermore I feel we would lack the same systems used today for social, political, and meaingful debate.
I guess you're being sarcastic. Without language how is there debate? There would be the limited communication of facial expression and body language that the other apes have. Notice that the apes who have been taught American Sign Language are so struck by the way it has enriched their own lives that they teach it to other apes.
If all languages were similar would we be more inclined to agree with one another, or would there still be a divide between us based on race?
Americans on the north and south side of the Mason-Dixon line speak virtually the same language and are of the same race, yet we disagree violently. The Irish have been speaking English for centuries and they don't agree with the English. People within the same family hate each other. Language is a tool for communication but it is not a magical talisman that creates harmony.
I'd have to ask whether language is a helpful, beneficial thing for mankind, or a negative force that drives a wedge between our cultures.
Language
is mankind. Without it Homo sapiens would just be tribes of hunter-gatherers like our closest relatives, the chimpanzees, bonobos and gorillas. It's just plain silly to talk about mankind in the absence of language.
Another concern is this... if language is unique to each culture then is their scientific knowledge, etc. built upon their ability to communicate through it? How much does language influence society?
Language is just one aspect of human culture. Language and the rest of a culture evolve together and influence each other.
Chinese has no verb tenses and therefore no conditional or subjunctive mode. It's said that makes it difficult to express speculative statements. Yet it does have a couple of different words for "if" and they seem to be all it takes to surmount the difficulty. German is hamstrung by an involuted syntax that often places the verb at the very end of a very long sentence. Yet Germans have had no trouble excelling in science and philosophy. Many foreigners feel ill at ease with English's lack of a formal form of "you," yet it doesn't bother us at all. We are befuddled by Japanese's ability to build a sentence with no subject, but they find it useful for constructing Zen parables.
All of these differences make a language seem charming or frustrating to outsiders and they give a moderate impetus to the shaping of its speakers' thoughts. Yet we have remarkably little difference translating the weightiest books from one to another.
Language helps reinforce diversity. I believe the richness that diversity has brought to the culture of our civilization is well worth the price we pay for it, in the form of the occasional misunderstanding.
As for the original question, whether language correlates with intelligence... Yes, the ability to communicate in language is the ability to think in language, and most people think predominantly in words. Without language we would be much lesser animals. But if the question is whether the accident of speaking one language rather than another gives an advantage in developing intelligence, I don't think there's any evidence of that. The range of IQ among humans is so broad that it would be impossible to factor out the influence of language even if it existed.
