They attempted to achieve extreme objectivity and frankness, presenting characters of low social and economic classes who were determined by their environment and heredity.

他们想达到极端的客观与直率，他们所展现的人物往往都是下层社会的人，他们的命运受到环境和遗传的制约。

So you can see that environment and heredity interact to affect intelligence, and that some tricky implications can come out of that conclusion.

所以你可以看到环境和遗传相互作用会影响智力，并且可以从该结论中得出一些棘手的含义。