I'm sure we've all heard the famous definition, 'Man is a rational animal', which I believe can be found in Aristotle's Nichomachean Ethics (though don't quote me on that, I'm more Platonic in my interests). In addition, Plotinus, St. Thomas Aquinas, and others have worked with a very similar definition (believe it or not, even Freud talked about it!). In the past, the emphasis was often on the first of these complements, that is, the rational aspect; perhaps the strongest example of this can be found in the philosophy of Immanuel Kant, both of whom lay heavy emphasis on reason and rationality. In more recent times, however, the emphasis has broadly shifted towards the second, namely, man as an animal.
This shift I find disturbing, not to mention largely uninteresting except for the concerns it raises. But first let me give a brief example of this rather base shift: on a bus home recently, I had the rather unusual experience of overhearing one girl ask the boy next her why he had not slept with anyone yet, despite being attracted to them. The boy evaded the question by asking why he ought to have done so, to which the girl replied that 'We are all just animals', and thus we should follow our needs. At this point the girl was getting off the bus, so I know not where the conversation would have led, but the complete conviction with which she made this statement struck me quite strongly. What, then, is the point of civilisation, what of art, what of language? Why need we speak, why not merely grunt, and, should I feel an attraction to a girl, why not simply throw her over the shoulder and be off with her?? Because, I am glad to say, I am not my body. To be sure, I am not my mind either, but rather the synthesis of the two, but what sets me apart as a person, rather than a mere beast, is my rationality, my mind and soul.
The very fact that we can disagree, the fact that this girl could hold this position and defend it to another, declares an inherent and inviolable distinction between humanity and those beasts which roam the plains. Actually, I just really wanted to make an allusion to beasts which roam the plains. Nevertheless, regardless of the phrasing, the point remains. It is simply self-refuting to declare ourselves animals, because an animal does not do so. There is a poignant remark made by the Seventh Doctor (6:13 of this video), played by Sylvester McCoy (who, incidentally, is Radagast the Brown Wizard in The Hobbit), in the Doctor Who episode, The Remembrance of the Daleks: "When is a cat not a cat? When it builds its own cat-flap." There is a fundamental difference between an animal and a person; yes, a person has that animal nature, and yes, one might even argue that is part of what makes that person, but it is only part, and therein lies the difference.