There are lots of stories about how philosophy begins. Some people claim it begins in wonder; some people claim it begins in worry. I claim it begins in disappointment.

There is something desperately lonely about Barack Obama's universe. One gets the overwhelming sense of someone yearning for connection, for something that binds human beings together, for community and commonality, for what he repeatedly calls "the common good". This is hardly news.

Melancholia for Freud is the relationship that the subject takes up with respect to itself from the position of what he calls conscience or what he later calls the super-ego. And that can be lacerated - if you think of the anorexic who sees themselves from the perspective of the image they have, of the image they have of themselves in the mirror which is false - that would be the super-ego. Super-ego is what generates depression and it is what has to be dealt with in psychoanalysis.

Genuinely great humour recognises the world it's describing and yet we are also called into question by it. That's what great art should do. That's what great philosophy should do. The one thing about humour is that this is an everyday practice that does this.

We must believe, but we can't believe. Perhaps this is the tragedy that some of us see in Obama: a change we can believe in and the crushing realisation that nothing will change.

When the animal becomes human, the effect is pleasingly benign and we laugh outloud, "Okay come clean now. This isn't really about hunting, is it?" But when the human becomes animal, the effect is disgusting, and if we laugh at all, then it is what Beckett calls the "mirthless laugh", which laughs at that which is unhappy.

The yearning for the common good comes from the refusal to accept that perhaps Americans have very little in common apart from the elements of a sometimes successful civil religion based around a sentimental, indeed sometimes teary-eyed, attachment to the constitution and a belief in the quasi-divine wisdom of the founding fathers.