Do humans try to find a mate who's different from them?

Ahaha, if humans are all conscious of that fact, then the entire population would be more immune :)

Recently I've read a book and it says that we're often attracted to people who are most genetically different from us. It's part of our instinct. So our natural behaviour of finding somebody who is genetically different from us reduces the chance of our children have double recessive diseases.

Once my bio teacher told me that your genes decide which people you are attracted to. Interesting isn't it. Maybe we should start supporting genetic determinism. Perhaps fate does exist after all.

You are thinking that humans are like other beings in the world. It is true, in a way, that many other organisms mate with another of their kind that would be most likely to produce offspring that would be better suited for their environment. However, humans are not like this anymore. The world that humans live in has been altered to such a degree from the natural world that other organisms live in that it is no longer absolutely necessary for one to find a mate that would produce the most viable offspring. Rather, a human can find a mate that is less likely to survive, and then fall in love, something that the lower order animals do not do. The fact that we have medicine and technology allows us to do this, so that way we don't have to produce children who are "immune to more different things". I hope you understand what I am trying to say here...

in a sense, yes. Humans can smell chemicals called pheromones that reveal certain traits about others without even realizing it. We subconsciously are attracted to mates who possess different immune systems then ourselves because that makes for stronger children.