Hive management in early spring to speed up brood production. Propolis is another byproduct of the bee hive. Certain races of bees are more prone to using propolis. Propolis can be collected on special plastic propolis screens. The tendency of the bees is to use propolis as a glue to seal openings that are too small for a bee to crawl through. A propolis screen is usually put in place of an inner cover. It has small openings that are propolized by the bees. The propolis screen can be frozen which hardens the propolis. Once the propolis is frozen it can be
Substance theory bundle theorist objects to the notion of a thing with no properties, claiming that such a thing is inconceivable and citing John Locke, who described a substance as "a something, I know not what." To the bundle theorist, as soon as one has any notion of a substance in mind, a property accompanies that notion. The indiscernibility argument from the substance theorist targets those bundle theorists who are also metaphysical realists. Metaphysical realism uses the identity of "universals" to compare and identify particulars. Substance theorists say that bundle theory is incompatible with metaphysical realism due to the identity of indiscernibles: