Rationalism is the emphasis on reasoning as a source of knowledge. Empiricism is the emphasis on observational evidence via sensory experience over other evidence as the source of knowledge. Rationalism claims that every possible object of knowledge can be deduced from coherent premises without observation. Empiricism claims that at least some knowledge is only a matter of observation.Logic is the study of the principles of correct reasoning. Arguments use either deductive reasoning or inductive reasoning. Deductive reasoning is when, given certain statements (called premises), other statements (called conclusions) are unavoidably implied. Rules of inferences from premises include the most popular method, modus ponens, where given “A” and “If A then B”, then “B” must be concluded. A common convention for a deductive argument is the syllogism. An argument is termed valid if its conclusion does follow from its premises, whether the premises are true or not, while an argument is sound if its conclusion follows from premises that are true. Propositional logic uses premises that are propositions, which are declarations that are either true or false, while predicate logic uses more complex premises called formulae that contain variables. These can be assigned values or can be quantified as to when they apply with the universal quantifier (always apply) or the existential quantifier (applies at least once). Inductive reasoning makes conclusions or generalizations based on probabilistic reasoning. For example, if “90% of humans are right-handed” and “Joe is human” then “Joe is probably right-handed”. Fields in logic include mathematical logic (formal symbolic logic) and philosophical logicOne debate that has commanded the attention of ethicists in the modern era has been between consequentialism (actions are to be morally evaluated solely by their consequences) and deontology (actions are to be morally evaluated solely by consideration of agents' duties, the rights of those whom the action concerns, or both). Jeremy Bentham and John Stuart Mill are famous for propagating utilitarianism, which is the idea that the fundamental moral rule is to strive toward the "greatest happiness for the greatest number". However, in promoting this idea they also necessarily promoted the broader doctrine of consequentialism. Adopting a position opposed to consequentialism, Immanuel Kant argued that moral principles were simply products of reason. Kant believed that the incorporation of consequences into moral deliberation was a deep mistake, since it denies the necessity of practical