Counting principle

A constraint on valid counting, such as stable ordering of number words, one-to-one correspondence with items and the cardinality principle. Understanding and coordinating these constraints should be distinguished from rehearsing a count routine.

The principle that the final number word in a valid count represents the cardinality of the whole collection. A child's knowledge of this relationship is different from merely repeating the last word after being prompted.

A description of which exact number-word meanings a child demonstrates in tasks such as giving a requested collection. Early knowledge of particular small quantities can precede a general use of the counting system; task context and errors matter when assigning the description.