Conditions vs Requirements

This investigation started from this phrase:

The difference between a logical condition and a requirement may be understood in terms of the (Kantian) difference between analytic statements (logical conditions) and synthetic statements (requirement). [Lehmann, J., Breuker, J., & Brouwer, B. (2004). Causation in AI and Law. Artificial Intelligence and Law, 12(4), 279–315] 

In philosophy these concepts are usually defined along these terms: analytic propositions are true by virtue of their meaning (eg. robins are birds), i.e. truth seems to be knowable by knowing the meanings of the constituent words alone; synthetic propositions are true by how their meaning relates to the world (eg. robins fly), i.e. truth is knowable by both knowing the meaning of the words and something about the world. (See Analytic/Synthetic Distinction on the Stanford Encyclopedia of Philosophy.)

However, conditions and requirements have a quite different meaning in other domains. For example, general conditions refer usually to an inherent part of an agreement. They are more static (considering a certain domain), and remain the the same from contract to contract, dealing with contractual principles. Supplements are added for a particular contract. On the other hand, general requirements cover an inherent part of the specifications of the contract: they are more dynamic because they change from contract to contract, and deal with minute specifications applicable to that particular case.

In that article the quoted phrase followed these statements:

In other words, the grounds for responsibility attribution do not have the status of logical or strictly rational conditions. They rather are widely accepted requirements, which generally grow out of tradition and that are progressively codified by legislators in the Law. [ibidem]

Integrating this, we may infer the following general rule: conditions come from (logic) necessity, requirements come from use. Considering the examples given above, we may explain the different uses in this way: 

• general conditions adhere necessarly to the current legal dispositions, while the description of the general requirements is a result of the expertises of the provider and user, 
• grounds for responsibility grow up with the legal production, so they are requirements,
• analythic propositions are logically necessary, while synthetic propositions result from our experience.