The fluent calculus is a formalism for expressing dynamical domains in first-order logic. It is a variant of the situation calculus. The frame problem is solved by asserting that the situation after the execution of an action is identical to the one before but for the conditions changed by the action. For example, the action of moving the box from the table to the floor is formalized as:

is commutative and non-idempotent are necessary for such axioms to work.

See also

• Fluent (artificial intelligence)

• Frame problem

• Situation calculus

• Event calculus

References

• M. Thielscher (1998). Introduction to the fluent calculus. Electronic Transactions on Artificial Intelligence, 2(3–4):179–192.

• M. Thielscher (2005). Reasoning Robots - The Art and Science of Programming Robotic Agents. Volume 33 of Applied Logic Series. Springer, Dordrecht.