How would one distinguish between what is meant by Mathematica's "Set" and "SetDelayed" functions in informal mathematical notation? Is there a way to make this distinction any any reasonably standard formal logics? Also, how is informal mathematical notation and formal logic notation related to Mathematica's use of variables like 'x\_'? Here is the relevant part of the Mathematica documentation:

<http://reference.wolfram.com/mathematica/howto/CreateDefinitionsForVariablesAndFunctions.html>