Other forms: irreducibly
Something irreducible is as simple, basic, or straightforward as it possibly can be.
How a certain person grows up to be a genius is irreducible to the sum of her experiences and genetic material — it's not that simple. And you might say that you can't generalize about your favorite poet, that her brilliant work is irreducible to such simplification. Irreducible is a big word, but it basically just means "you can't make it any simpler than this."