What is the concept of strong emergence and how does it differ from weak emergence in the field of philosophy?

Strong emergence is the idea that complex systems can exhibit properties or behaviors that cannot be explained by their individual parts. This means that the whole is more than just the sum of its parts, and new properties emerge at a higher level of organization. Weak emergence, on the other hand, suggests that the properties of a complex system can be explained by the interactions of its individual parts, without the need for any additional emergent properties.