The distance between the actual developmental level as determined by independent problem solving and the level of potential development as determined through problem solving under adult guidance or in collaboration with more capable peers

The specifically human capacity for language enables children to provide for auxiliary tools in the solution of difficult tasks, to overcome impulsive action, to plan a solution to a problem prior to its execution, and to master their own behavior.

It is through others that we become ourselves.

Learning is more than the acquisition of the ability to think; it is the acquisition of many specialized abilities for thinking about a variety of things.

The child begins to perceive the world not only through his [or her] eyes but also through his [or her] speech

Through others we become ourselves.

Thought is not merely expressed in words, it comes into existence through them