Language is the tool of the tools

Every function in the child's cultural development appears twice: first, on the social level, and later, on the individual level; first, between people (interpsychological) and then inside the child (intrapsychological). This applies equally to voluntary attention, to logical memory, and to the formation of concepts. All the higher functions originate as actual relationships between individuals.

Any human act that gives rise to something new is referred to as a creative act, regardless of whether what is created is a physical object or some mental or emotional construct that lives within the person who created it and is known only to him.

... People with great passions, people who accomplish great deeds, people who possess strong feelings, even people with great minds and a strong personality, rarely come out of good little boys and girls.

A word devoid of thought is a dead thing, and a thought unembodied in words remains a shadow.

The only 'good' learning is that which is in advance of development.

A child’s greatest achievements are possible in play, achievements that tomorrow will become her basic level of real action.