Along with the inability to take a general view of the beliefs he held, and to reduce them to a philosophic system, went an inability to form abstract ideas. This inability, again, may be traced to natural causes. Thanks to the perpetual sunshine of the valley of the Nile, the Egyptian leads an open-air life. Except for the purpose of sleep, his house is of little use to him, and in the summer months even his sleep is usually taken on the roof. He thus lives constantly in the light and warmth of a southern sun, in a land where the air is so dry and clear that the outlines of the most distant objects are sharp and distinct, and there is no melting of shadow into light, such as characterises our northern climes. Everything is clear; nothing is left to the imagination; and the sense of sight is that which is most frequently brought into play. It is what the Egyptian sees rather than what he hears or handles that impresses itself upon his memory, and it is through his eyes that he recognises and remembers. At the same time this open-air life is by no means one of leisure. The peculiar conditions of the valley of the Nile demand incessant labour on the part of its population. Fruitful as the soil is when once it is watered, without water it remains a barren desert or an unwholesome marsh. And the only source of water is the river Nile. The Nile has to be kept within its banks, to be diverted into canals, or distributed over the fields by irrigating machines, before a single blade of wheat can grow or a single crop be gathered in. Day after day must the Egyptian labour, repairing the dykes and canals, ploughing the ground, planting the seed, and incessantly watering it; the Nile is ready to take advantage of any relaxation of vigilance and toil, to submerge or sweep away the cultivated land, or to deny to it the water that it needs. Of all people the Egyptian is the most industrious; the conditions under which he has to till the soil oblige him to be so, and to spend his existence in constant agricultural work. But, as I have already pointed out, this work is monotonously regular. There are no unexpected breaks in it; no moments when a sudden demand is made for exceptional labour. The farmer’s year is all mapped out for him beforehand: what his forefathers have done for unnumbered centuries before him, he too has to do almost to a day. It is steady toil, day after day, from dawn to night, during the larger portion of the year. This steady toil in the open air gives no opportunity for philosophic meditation or introspective theorising. On the contrary, life for the Egyptian _fellah_ is a very real and practical thing: he knows beforehand what he has to do in order to gain his bread, and he has no time in which to theorise about it. It is, moreover, his sense of sight which is constantly being exercised. The things which he knows and remembers are the things which he sees, and he sees them clearly in the clear sunshine of his fields.