What you’re talking about are the three poisons which in Buddhism are what is said to cause one to suffer. They are greed, ignorance and hatred, not delusion. And agreed, it’s these three aspects that cause us to suffer, but these are natural human traits which even the Sangha feel. It’s only when you reach a level of enlightenment that you will be able to let go of these three aspects. However, before considering the three poisons, one has to consider the 5 precepts which is the core of Buddhism. And if every word is taken in a very theoretical and literal sense, and not applied to the real world, that in itself is the very definition of delusion. One becomes very rigid in their thinking process and cannot consider other points of view. The Buddha encouraged lay people such as ourselves to explore for ourselves our own truth and what it means to us individually with an open mind.