Labour is, in the first place, a process in which both man and Nature participate, and in which man of his own accord starts, regulates, and controls the material re-actions between himself and Nature. He opposes himself to Nature as one of her own forces, setting in motion arms and legs, head and hands, the natural forces of his body, in order to appropriate Nature’s productions in a form adapted to his own wants. By thus acting on the external world and changing it, he at the same time changes his own nature. He develops his slumbering powers and compels them to act in obedience to his sway. We are not now dealing with those primitive instinctive forms of labour that remind us of the mere animal.
In the last article we mentioned that tool-making was the dividing line between humans and animals. We may be more specific and say that the key process that propelled our evolution and made tool-making possible was labour.
Engels argued that labour was what helped to form the human hand and brain:
Labour is the source of all wealth, the political economists assert. And it really is the source — next to nature, which supplies it with the material that it converts into wealth. But it is even infinitely more than this. It is the prime basic condition for all human existence, and this to such an extent that, in a sense, we have to say that labour created man himself.
Labour became possible because our primate ancestors adapted to the grasslands by walking erect, which in turn freed their hands. The very first tools were found objects, mostly stones: crude extensions of the hand useful for cutting or pounding. As early humans discovered how to put these objects to use, for example to extract the nutritious marrow from bones, their hands and brains evolved to the point where they could make tools of their own. The development of the opposable thumb gave them unprecedented dexterity, and they developed excellent eye, hand and brain coordination. Engels concluded:
Thus the hand is not only the organ of labour, it is also the product of labour. Only by labour, by adaptation to ever new operations... has the human hand attained the high degree of perfection that has enabled it to conjure into being the paintings of a Raphael, the statues of a Thorwaldsen, the music of a Paganini.
The hands of the most primitive humans can create objects that no other animal is able to. Thus our labour distinguishes us from animals, as Marx explained in the 1844 Manuscripts:
It is true that animals also produce. They build nests and dwellings, like the bee, the beaver, the ant, etc. But they produce only their own immediate needs or those of their young; they produce only when immediate physical need compels them to do so, while man produces even when he is free from physical need and truly produces only in freedom from such need.
And in Capital:
The use and fabrication of instruments of labour, though we find their first beginnings among certain other animal species, is specifically characteristic of the human labour process...
It is through thousands of years of labour (i.e. active material engagement with our environment) that our ancestors made the extraordinary leap from primate to human. This is a process that many evolutionary scientists — including Darwin himself — have failed to grasp. Even such evolutionary factors as the consumption of meat and the adaptation to cooked food require both labour and tool-making. Culture has played so important a role that, as the archaeologist Timothy Taylor has pointed out, we cannot live without artificial aid:
Humans would die without tools, clothes, fire, and shelter... I believe that from the very start our early ancestors took control over their own evolution by developing technologies... 
To understand this leap fully we must explore the dialectical relationship between labour and the advent of a uniquely human consciousness.
The expanding consciousness
Engels’ singular emphasis on the freeing of the hand by bipedality has become dated, but most archaeologists would agree that tool-making is the ability that marks the appearance of the first humans, the habilines. The hand is one important part of a complex organism, advances in one part of which had consequences and benefits for the whole.
Tools enabled human beings to make the transition from scavenging to hunting and fishing. This allowed an expansion of their diet and greater efficiency in food-gathering, which increased the nutrients going to the brain. Our brain increased in size and complexity. But our consciousness is not a merely biological process. As humans became aware of the different properties of the found objects they used as tools, they refined them to make the objects more effective. They realised that a piece of flint picked up from the ground does not usually cut a hide as well as one that they had, by accident or design, knocked into an edge.
When we compare the tools of succeeding eras we see increasing precision, effectiveness and sophistication, and apparently a developing aesthetic sense. Oldowan tools were mostly created simply by splitting a stone into two to create a cutting edge. The handaxes which appear in the time of Homo erectus take many forms, but include examples that are ovate, symmetric and finely formed.
Acheulean handaxe in a tear-drop shape discovered in Spain, dating to c.350,000 years ago. Acheulean tools represent a utilitarian, and, at least to us, an aesthetic, advance on the Oldowan.
Whether humans were making aesthetic decisions at this stage in their evolution is open to debate. A number of anthropologists have argued that symmetry in handaxe design may simply be more efficient  — i.e. any artistic value may be in our eyes rather than their creators’. The truth probably lies inbetween: early humans were developing the rudiments of an aesthetic sense which only Homo sapiens was to master. (See our article on the origins of symbolic representation.)
“Creative consciousness,” wrote Ernst Fischer, “developed as a late result of the manual discovery that stones could be broken, split, sharpened, given this shape or that.” Modern archaeology does not contradict him. By slowly discovering how to use natural materials to achieve their purposes, such as lighting a spark or cracking open a shell, the human mind was being encouraged to encompass new intellectual concepts.
Animals participate in nature just as we do, and like us their actions can change it. Engels  uses the example of animals grazing the vegetation in an area and, because they do not know what they are doing, destroying the food source, compelling them to move on to new areas. If humans raze an area of vegetation they do it in order to plant crops or introduce some other premeditated development. This is not to say animals are incapable of premeditation, planning or cunning, simply that they have never taken the evolutionary step necessary to impose their will upon nature. Engels concludes:
The animal merely uses its environment, and brings about changes in it simply by its presence; man by his changes makes it serve his ends, masters it. This is the final, essential distinction between man and other animals, and once again it is labour that brings about this distinction.
Other animals use tools — chimpanzees for example know how to poke a stick into a termites’ nest, so that they can draw the stick out and eat the termites on it. But there is a difference between picking up and using a naturally occurring object, and transforming that object through labour. Early humans had to be capable of projecting their actions beyond the present, foreseeing the outcome of their labour and the benefits it would give them, to take that crucial step to tool-making which no other animal has made.
It is through labour and the production of tools, with the increased demands on the dexterity of both hand and mind, that we became aware of our actions, and our hands and senses became human. Fischer uses the example of an ape using a stick to get fruit from a tree. The ape sees the fruit and, knowing that a stick can be used to fetch it down, will look around for one. After many repetitions, the ape finally makes an intellectual leap: “here is the stick, where is the fruit it can fetch down?”
Thus it was that Fischer could conclude that “the hand released human reason and produced human consciousness.” Not, as we have said, the hand alone, but the hand in dialectical combination with other processes.
Man took the place of nature. He did not wait to see what nature would offer him: more and more he forced it to give him what he wanted. He made nature more and more his servant. And out of the increasing usefulness of his tools, out of their increasingly specific character, out of their increasingly successful adaptation to the human hand and the laws of nature, out of their increased humanisation, objects were created which could not be found in nature.
We shall see the further significance of the creation of non-natural objects in the article on the humanisation of nature. As humans embarked upon the Neolithic Revolution, even plants and animals were transformed by labour, via deliberate breeding to meet human needs. This has been taken to the point where the modern milch cow has become both extraordinarily productive and incapable of surviving without human support.
Our consciousness developed out of a process of labour that began with the primitive use of found objects and, through a long interaction of evolution, exploration and adaptation, culminated in human-made objects that include works of art.
In a footnote in Capital, Marx comments on Benjamin Franklin’s definition of humanity as a ‘tool-making animal’ as being “characteristic of Yankeedom”. It is true that tool-making characterises human production, but Marx takes issue here with the idea that our uniqueness can be reduced to technology, to instruments of profit.
The universe is made of processes which interact constantly with one another — as we change nature, nature changes us; as we produce labour, labour produces us. By working the raw stuff of nature we discovered through a social and biological dialectic our own capabilities as humans: physical, intellectual and creative. This relationship is the soil from which art could grow.
 Karl Marx, ‘The Labour-Process And The Process Of Producing Surplus-Value’ from Capital, vol. 1 (1867).
 Engels, The Part Played by Labour in the Transition from Ape to Man (1876).
 Marx, ‘Estranged Labour’ from the first of the Economic and Philosophic Manuscripts of 1844 (1844). First published in 1932, these manuscripts of a work Marx planned on bourgeois political economy are only in draft, fragmentary form and are therefore less harmonious in content and style than his finished works. Despite this they offer an invaluable insight into his ideas on aesthetics.
 Marx, ‘The Labour-Process And The Process Of Producing Surplus-Value’ from Capital, vol. 1 (1867).
 Timothy Taylor, The Artificial Ape: How Technology Changed the Course of Human Evolution (2010).
 See for example page 6 of April Nowell and Melanie Lee Chang, ‘The Case Against Sexual Selection as an Explanation of Handaxe Morphology’, PaleoAnthropology (February 2009). This article is principally a refutation of Steven Mithen’s theory that handaxes were made beautiful by men in order to attract women, which is one of his less useful ideas.
 Fischer, The Necessity of Art (1959). Ernst Fischer was an Austrian Marxist prominent in the rediscovery of ‘humanist’ Marxism in the period of de-Stalinisation. This book offers a good account of the development of humans through labour.
 Engels, op. cit.
 Engels, op. cit. This is not an excuse for species arrogance, a point made by Engels himself. Humans’ unique capacity to exploit the laws of nature is producing, for example, the disaster of global warming, which not only threatens the existence of other species but the lives of thousands of our own. On the other hand, our mastery of the laws of nature are constantly improving through scientific inquiry.
 Well, almost. Recent research suggests that humans are not strictly unique in their tool-making (see for example Betty the crow). Such achievements in animals however simply emphasise the poverty of their tool-making ability compared to our own. Betty made a hook out of wire — she did not build a Sputnik.
 Fischer, op. cit.
 Footnote to Chapter 13 of Capital, vol. 1 (1867). ‘Yankeedom’ implies a vigorous capitalism that seeks to commodify everything.