Immanuel Kant, who lived from 1724 to 1804, held a great respect for the Scottish philosopher David Hume (1711-1776), many of whose ideas he holds in extremely high regard. His moral and ethical beliefs are most formally set out in his three works The "Foundations of the Metaphysics of Morals" (1785), the "Critique of Practical Reason" (1788), and the "Metaphysics of Morals" (1798) and hold strong links with Hume's Philosophy, much of which he was inspired by to write his later treatises. Kant was caught between the two philosophical traditions of rationalism, more prevolent on the continent at the time, and empiricism, a school of thought mostly constituting British thinkers such as Berkeley, who was Irish, Hobbes, and Locke. Hume also figures amongst notable empiricists.

Loosely, rationalism is defined as being the belief that our knowledge is derived from purely rational means. The greek philosophers - most notably Plato - were protaganists of this school of thought. As Plato remarked, "all that you get from experience.. is mere opinion". Empiricism, on the other hand, believes that everything we know, and all of the 'contents of our consciousness' derive from experience, and that there are in fact no innate concepts or ideas. We cannot escape, says the empiricist, from the fact that our statements derive from what we have perceived. John Locke's 'tabula rasa' (blank table) exists as a metaphor for the human mind at birth, which is acted upon by the world to form the set of experiences and beliefs which constitute our character and sensibilities later on in life.

Kant's philosophy is systematic, touching on practically every aspect of philosophy with one broad, coherent, all-embracing system, and appears to take values from both empiricism and rationalism, whilst at the same time offering what might be considered to be a third option, much as Bertrand Russell seems to play off the two schools against each other to form a picture of our acquisition of knowledge which uses both and rests concretely on neither.

Although Kant wrote philosophical texts for much of his life, it was - as hinted at above - his encounters with David Hume which caused him to undergo a radical thinking of his philosophy, and much of his philosophy - particularly his negative account* of morals. Kant refers to his philosophy prior to 'The Critique of Pure Reason' as his pre-critical philosophy, and the work after it as his critical philosophy, even going so far as to state that his pre-critical philosophy is little more than 'dogmatism'. "common sense is the business of the philosopher", says Kant, and we ought to question the self-evidence, often tied in with such phrases as 'intuition' and 'common sense' which sceptics use as dismissals of much philosophy.

Hume's Positive Account* of morality is most cogently set out in his fourth book, 'An Enquiry Concerning the Principles of Morals', which he wrote in the year 1751. Hume considered the book to be his best work by a considerable margin, and certainly constitutes a superb presentation of his philosophy. Hume's positive account of morality has been interpreted as emotivism*, but a close reading of it is both extremely beneficial in understanding Kant's morality, and dispels this rumour. Essentially, Hume says, morality is more properly felt than judged. He states that "We do not infer a character to be virtuous because it pleases, but in feeling that it pleases, we feel it to be virtuous", and this is only the case - Hume states - when disregarding our own interests and neutrally observing actions. We base morality on perceiving negative emotions and condemning them, and perceiving positive ones and promoting them. Goodness and badness simply consist of how people react, and this is what morality consists of, assuming a commonality in our (admittedly, varying) approaches to morality.

For Kant, however, this account of morality is not sufficient to provide a basis for moral obligation, which is what all morality seeks to do (ie. simply, if we believe in divine command theory (divine command theory, simply, states that our morals derive from divine command (or 'the word of god')), We are obliged not to kill, for example, simply because god says we shouldn't.) because, he states, emotions are contingent in that they are not universal: emotions change from person to person, and in doing so, have variations and exceptions, therefore not providing any adequate grounds for moral belief. This is true, Kant says, for any moral theory which appeals to the emotions, the good of humanity, the desires, shared moral beliefs, or any consequentialist theory.

In order for moral laws to be universal, therefore, Kant states that our moral theories have to be based on immutable, concrete ideas, and these only exist a priori, or independantly of experience, Kant states. (as opposed to a posteriori, or from experience.) Kant, therefore, advocates an a priori basis for morality, deriving from REASON.

Kant elaborates in a step which brings us gradually closer to the core of his positive account of ethics. Reason when applied to the empirical world, Kant states, relies on contingency, as expounded above: there is, therefore, no basis for morality here. In order to derive an a priori basis for morality, therefore, Kant has to find another form of reason. He does this cleverly: his first step is to carefully define the parameters by which he defines previous attempts at ethical theorising. Hume's negative account, he postulates, refers to what he denotates theoretical reason. Theoretical reason refers to our beliefs (or what is "binding on us as cognitive beings"). As Kant said, "nature would have made a mistake, in choosing wellbeing as our goal, in choosing our reason as the source of morality", ie. (this form of) reason is inadequate for the task in hand (that of constructing a system of moral philosophy). Instead, Kant states, theoretical reason is a practical tool given to us in order that we may apply it to the world around us and live profitably as a result. Practice of it in the pursuit of philosophy, further to this, develops misology, or the 'hatred of reason', which he seems to suggest was Hume's cause for ultimately choosing common moral understanding as the basis for ethics.

Moral philosophy, the field of which we are concerned (or 'what ought to happen'), and also Natural Philosophy (the sciences, or 'what does happen') are both concerned with both reason and the senses, but in order to be a truly a priori theory, Kant needs to isolate solely the reasonable aspect of this, and therefore moves onto his second type of reason, practical reason, which he says can influence our actions, whilst at the same time being free of contingency.