Is there a Need to Believe that Infants are Able to Calculate Exactly?

In a complement to the discussion by Stéphan Desrochers, the author argues that his own observations on 3, 4 and 5-year-olds are difficult to understand under the hypothesis of number and calculation in infants. Furthermore, infant’s behaviours, apparently numerical, may be explained by the dynamics of habituation or attention. Therefore there is no need to believe that infants are able to calculate exactly as claimed by Wynn.