What is the difference between deontology and teleology in ethics?

They are two different ways of justifying an ethical claim or view. An ethical claim might be, for example, "you should not eat meat." All ethical claims can be justified by both deontology and teleology. So what's the difference?Deontology is from the Greek "deon", meaning duty or necessity. If you justify an ethical claim using deontology, you argue that there is some duty or responsibility on people, and this duty necessitates or demands that they do such-and-such in order to fulfil it. This is why deontological justification often produces less flexible ethical systems: it sets out what you must do.Teleology is from the Greek "teos", meaning end or aim. If you justify an ethical claim using teleology, you argue that your ethical claim will lead to better end results or outcomes. This tends to make teleological ethics more flexible: because as long as you reach the goals, the means of getting there isn't fixed in advance.