Mfumo wa jamii katika zama yoyote ile ni matokeo ya hali ya kiuchumi. Mabadiliko yanayoathiri mfumo huu yote yanatokea kama matokeo ya mapambano ya kitabaka ili kuboresha hali yao ya kimaada. Historia inatuambia kwamba mapambano haya huishia kwa ushindi wa tabaka lenye idadi kubwa zaidi na hali mbaya zaidi, dhidi ya tabaka tajiri lenye idadi ndogo. Yeye aliliita hili sheria ya mageuzi ya kijamii. Sheria hii inatumika kwa siku zijazo pamoja na zilizopita. Hivyo, katika zama zilizopita mapambano haya yalikuwepo kati ya watu huru na watumwa, kisha kati ya wakuu na raia, baadaye kati ya wakuu na wakulima (wakulima wa mashamba), na kati ya viongozi na wakuu wa madhehebu. Mapambano haya daima yalimalizika kwa ushindi wa tabaka lililodhulumiwa, ambalo lilikuwa na idadi kubwa zaidi, dhidi ya tabaka la wadhalimu, lenye idadi ndogo. Lakini baada ya ushindi wake, tabaka lililodhulumiwa liligeuka na kuwa tabaka dhalimu la kihafidhina. Tangu Mapinduzi ya Ufaransa, mapambano haya yamekuwepo kati ya tabaka la kati (Bourgeoisie) na tabaka la wafanyakazi. Tabaka la kwanza likawa mabwana wa miradi ya kiuchumi, wamiliki wa mitaji, na likawa la kihafidhina. Likikabiliana nalo ni tabaka la wafanyakazi ambalo halimiliki chochote cha mtaji, lakini lina idadi kubwa zaidi. Kwa sababu hiyo, hali hii imesababisha mgongano wa maslahi kati ya matabaka haya mawili, ambao chimbuko lake limejengwa juu ya sababu za kiuchumi. Mtindo wa uzalishaji wa leo hauendani na mfumo wa umiliki. Uzalishaji haubaki tena wa kibinafsi, yaani unaofanywa na mtu mmoja peke yake, kama ilivyokuwa katika zama zilizopita, bali umekuwa wa kishirikia, yaani unaofanywa na watu wakiwa pamoja. Wakati huo huo, hata hivyo, mfumo wa umiliki haujabadilika. Hivyo umiliki wa kibinafsi unaendelea na bado ni msingi wa mfumo katika jamii ya sasa. Kutokana na hili, tabaka la wafanyakazi, linaloshiriki katika uzalishaji, halina sehemu katika umiliki wa mtaji, na linabaki chini ya huruma ya Wakapitalisti (wamiliki wa mtaji), ambao wenyewe hawashiriki katika uzalishaji. Wakapitalisti wanawanyonya nguvu kazi, wakiilipa ujira wa kujikimu tu, nao wafanyakazi wanalazimika kukubali kwa sababu hawana chochote isipokuwa juhudi zao za kujitegemeza. Tofauti kati ya thamani ya bidhaa na ujira wa kazi, ambayo Marx anaiita thamani ya ziada, ndiyo faida ambayo Mkapitalisti anaimiliki peke yake, ilhali haki inadhania kwamba inapaswa kuwa sehemu ya wafanyakazi.
The system of the society in any age is a result of the economic situation. The transformations which affect this system all come as a result of a class struggle to improve their material situation. History tells us that this struggle ends with the victory of the class which is greater in number and worse in condition, over the wealthier class which is fewer in number. He called this the law of social evolution. It applies to the future as well as the past. So, in previous ages this struggle existed between the freemen and the slaves, then between the nobles and the subjects, then later on between the nobles and the serfs (peasants), and between the leaders and chiefs in the order of sects. This struggle always ended with the victory of the oppressed class, which was greater in number, over the oppressor class, which was smaller in number. But after its victory the oppressed class turned to become a conservative oppressor class. Since the French revolution this struggle existed between the middle class (Bourgeoisie) and the working class. The first class became the masters of the economic projects, the owners of the capital, and became conservative. Facing it was the working class which owned nothing of the capital, but was much greater in number. Consequently, this situation led to a conflict of interest between the two classes, the origin of which was based on economic reasons. The production fashion today, does not conform to the system of ownership. Production no longer remains individualistic i.e. being performed by the person alone, as it was in past ages, but rather has become associative i.e. conducted by individuals together. At the same time however, the system of ownership has not changed. So individual ownership continues and is still the basis of the system in current society. As a result of this the working class, which participates in production, does not have a share in the ownership of the capital, and remains under the mercy of the Capitalists (the owners of the capital), who do not by themselves participate in production. The Capitalists exploit the labour force, paying it only subsistence wages, and the workers are compelled to accept it since they have nothing but their efforts to sustain themselves. The difference between the value of the product and the labour wage, which Marx calls the surplus value, constitutes the profit which the Capitalist monopolises, while justice assumes it should be the share of the workers.