Lev S. Vygotsky

What children can do with the assistance of others might be in some sense even more indicative of their mental development than what they can do alone

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

It may be said that the basic characteristic of human behavior in general is that humans personally influence their relations with the environment and through that environment personally change their behavior, subjugating it to their control.

Language is the tool of the tools

There is reason to believe that voluntary activity, more than highly developed intellect, distinguishes humans from the animals which stand closest to them.

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

The true direction of the development of thinking is not from the individual to the social, but from the social to the individual.

Pedagogy must be oriented not to the yesterday, but to the tomorrow of the child's development. Only then can it call to life in the process of education those processes of development which now lie in the zone of proximal development

Writing should be meaningful for children, Y an intrinsic need should be aroused in them, and Y writing should be incorporated into a task that is necessary and relevant.

Psychology teaches us at every step that though two types of activity can have the same external manifestation, whether in origin or essence, their nature may differ most profoundly.