In southern Africa, a great many figures are ithyphallic. This feature has generally – and rather vaguely – been taken to refer to ‘masculinity’, but the painted contexts of the figures seems to confirm that, as in North America, sexual arousal was a metaphor for altered states of consciousness.

Shamanism is not simply a component of society: on the contrary, shamanism, together with its tiered cosmos, can be said to be the overall framework of society.

Perhaps the most striking feature of the west European Upper Palaeolithic, one on which many writers comment, is a sharp increase in the rate of change. Compared with the preceding Middle Palaeolithic, a great deal happened in a comparatively short time.

The notion that an image is a scale model of something else (say, a horse) requires a different set of mental events and conventions from those that perceive the social symbolism of red marks on someone’s chest.

Around 30,000 years ago, in the Aurignacian, at the beginning of the Upper Palaeolithic, someone or some group in the Eyzies region invented drawing, the representation in two dimensions on the flat of the stone of what appeared in the environment in three dimensions.

Seeing’ two-dimensional images is therefore something that we learn to do; it is not an inevitable part of being human.

Consciousness has evolved biologically and can therefore be explained biologically.

The cerebral cortex, the outer ‘skin’ of the brain, contains as many as ten billion neurons. This complexity is daunting. Yet it is out of complex interactions between the billions of neurons that consciousness arises.

Primary consciousness is a state of being aware of things in the world – of having mental images in the present.But it is not accompanied by any sense of a person with a past and future…