The newborn is completely dependent on the adults who care for it. But in the first years of life, it takes enormous developmental steps, all of which are directed towards its autonomy.
The child's "work" at this age is to build itself up. At the same time, it is a period of adaptation to its environment. Maria Montessori describes very impressively how this adaptation takes place in the infant: It unconsciously absorbs all the impressions in its environment - language, sounds, smells, etc. - in their entirety: these become an integral part of its personality. Montessori called this special mental characteristic of the toddler the "absorbent mind". Only later, from about 3 years of age, will it order these impressions and make them conscious through its own work.
Maria Montessori referred to the newborn as the "spiritual embryo" and stated: "Just as the physical embryo needs the special environment of the womb, the spiritual embryo also needs the protection of a living environment, warmed by love, rich in nourishment, in which everything is set up to promote its growth and nothing stands in the way". 
These insights guide us in the prepared environment in the Nido for the child in its first years of life.