system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why did nature make us intelligent instead of strong?
gpt
We are actually quite large and strong.  We are not as strong as some other primates, but we have a lot more stamina, and we can run farther (although not faster) than just about any land animal in existence.  While we lack the innate weapons of other large predators, we can still kill many smaller animals with our bare hands or with extremely simple tools.

The theories behind the evolution of intelligence are varied.  One idea is that at some point intelligence became sexually attractive and so increased over time.  A similar theory states that intelligence was used to succeed in complex social environments, and so more intelligent individuals would have more progeny.

So, to answer your question, we are reasonably strong and have incredible stamina and intelligence.  Some scientists have proposed that the shift from strength to stamina (relative to other large primates) occurred when our primate ancestors left the forest and began living in grassland environments.