One of the central paradoxes with which we are confronted in non-linear thinking is that of emergence. It can be formulated as follows: while a whole is generally thought of as a sum of its parts, a spontaneous generation of properties that do not belong to the parts seems to occur in the non-linear passage of the parts to the whole. This compels us to re-examine with greater philosophical care the seemingly simple categorical couple of whole/parts, where the whole — to paraphrase Kant — is any kind of multiplicity taken as a unity.