Children also gain an insight into the conservation of numbers, mass, and weight; which allows them to understand that just because the image of object changes that does not mean the nature of the object has to change with it. For example, children in this stage can tell that a cup of water is the same amount despite being poured into two different cups. Children also learn to classify objects by several features based on increased schemes from more external stimuli. Finally, the formal operational stage represents the state of the mind from eleven years onward. In this, there is logical abstract thinking, which goes beyond the child's immediate environment and incorporates abstract concepts. Children learn to test hypothesis using reason and the human mind looks forward into the future and the abstract hypothetical. According to Piaget, these stages are universal and occur within every individual. There is another side to the argument, however, that posits the concept that development is not necessarily universal, but is instead dependent on cultural and social influences. This is the main concept in Lev Vygotsky's view of cognitive development. Based on the premise that Piaget's universal model has too many internal inconsistencies, Vygotsky believed that there could be no absolute and concrete universal standards for such varied psychological developments seen in the wide context of cultures and societies existing simultaneously. According to Vygotsky, culture is key in interpersonal communication; "There are dialectal relations between social and individual levels which allow for levels of explanation without direct reduction of one to another," (Daniels 2005:10). Animals do not have the same kind of consciousness as humans; therefore consciousness does not seem to stem from biology. If it did, animals would have the same access o such higher thoughts. What separates humans from animals is culture and societies, therefore that must be the root of this elevated cognitive development; "Emphasizing the need to explain rather than merely describe psychological processes that are unique to human beings, Vygotsky argued that they have their source not in biological structures or the learning of the isolated individual but in historically developed socio-cultural experience," (Minick 2005:36). Thus it is the existence of culture in human societies that is the strongest influence on the development of the mind according to Vygotsky.

This idea of the strength of nurture over nature posits the idea that social interactions influence the cognitive development of a child. Adults, and especially parents, are largely responsible for the development of the child's psyche, for the child learns to emulate them in order to live within society. This then has a huge influence on the way the child perceives and thinks about the world. Thus development spurs from the process of cultural mediation. For example, a child can only describe the world in terms that he or she has been exposed to. Thus, "children's grasp of the reference of color terms does not properly stabilize until they have worked out the basic contrastive relations among the terms," (Daniels 2005:11). Color is just one element out of a plethora of others which shows that children's responses to their environment are directly influenced by the nature of that environment. Thus, "research must not focus on the development of individual mental functions but on the development of new relationships between mental functions, on the development of psychological systems that incorporate two or more distinct functions," (Minick 2005:34). This the main aim within a more culturally based theory of psychological development.

Such social interaction allows the child to adopt the culture, including speech patterns, written languages, and other symbolic knowledge. Vygotsky explained the idea of such communications as an instrumental act; "What is novel, artificial, and instrumental about the new connection is the fact that an artificial direction is given to the natural process by means of an instrument," (Minick 2005:36). Thus, the child learns instruments from within his or her society and then begins to implement them within the context of each individual experience to replicate a desired result first seen by watching other members of that culture. According to Vygotsky's interpretation the" higher mental functions rely on the mediation of behavior by signs and sign systems, the most important of which is speech," (Minick 2005:37). Thus, language is a tool learned and then adopted by the child by social interaction. It teaches them how to interact and get what they want by expressing themselves...

Therefore, "higher voluntary forms of human behavior have their roots in social interaction, in the individual's participation in social behaviors that are mediated by speech," (Minick 2005:38). Speech becomes the primary tool for the child to understand and engage in both the physical and social world around him or her. Learning new ways of expression then becomes a way to expand the child's experience of the external world. New words mean a larger understanding and role within the context of one's own life; "use of the word constitutes the formation of a new functional relationship between memory and speech, the formation of a new psychological system," (Minick 2005:34). The child first learns to implement the use of language in simple terms, and begins with what is known as self-talk. This is basic and unregulated speech that does not necessarily follow the exact guidelines of more complex cultural speech patterns. However, this stage ends when the kid enters school, where the child must learn to communicate in a more formal and socially acceptable manner. Once this is understood, then there is a difference between inner speech and social speech. The child uses these two lines of communication to regulate activity and mediate thoughts; "Vygotsky argued that the phonetic and grammatical abbreviation of inner speech as well as its non-vocalized character, emerge in connection with a change in the function of speech from the mediation of social behavior to the mediation of individual behavior," (Minick 2005:43). This represents the child's development into higher level cognition and role playing within a constraining and demanding culture.
This theory also rests on the idea of internalization. According to Vygotsky's initial beliefs, this is "knowing how" using the tools of society to figure out how to do things, like ride a bike or express oneself properly within different contexts. The child then takes the tool and adopts it as his or her own, constantly using it within the context of his or her own every day life. Thus it is clear that "the development of psychological constructs that allow consciousness and behavior to be conceptualized as aspects of a unified whole," (Minick 2005:36). Such practices are engaged by children through their practice of play. The concept of the Psychology of Play posits that children's games are crucial in psychological development. A prime example is the vision of the child wanting to ride a horse, but not being able to. Younger children will react in a particular manner, if child can't ride horse under three years old, the kid gets angry and throws a tantrum. However, after three the child understands that he or she must use different tools to get what the want, i.e. bargaining or using pretend play of riding a horse. Whatever object the horse is pretended to be hen becomes a pivot; "It is only within the activity of play that the child can substitute one object for another in this way, only with the activity of play that then begins to separate the object's meaning from the object itself by using another object as a pivot," (Minick 2005:48). Thus, play is a transitional stage of self-regulation and abstract representation. Play allows the child to attribute different ideas and concepts on to other objects. This allows the beginning of abstract thought, for "Vygotsky had represented play and imagination as a product of the power of speech to free behavior and thought from the domination of the immediate perceptual field," (Minick 2005:47). According to this concept, "thought and meanings are liberated from their origins in the perceptual field, providing the foundation for further development of speech and its role in advanced forms of thinking and imagination," through the enjoyable use of play (Minick 2005:47). Thus, the social atmosphere is crucial to the development of the child.

Finally, this theory posits the idea that guided participation can then guide cognitive development. There are three types of mediation: signs and symbols, individual activities, and interpersonal relations (Daniels 2005:8). Guiding a child can help that child emulate the social and cultural factors that then dominate his or her development. The Zone of Proximal Development represents tasks that are too complex for a child to do one his or her own. These tasks are then guided or assisted by a parent, adult, or older child. Guiding the child is then akin to setting up scaffolding for them to use in the building of their own minds. According to research, "The scaffolding interpretation is one in which a distinction is made between support for the initial performance of tasks…