Full Idea
Burke argues that Tib (the whole cat apart from its tail) goes out of existence when the tail is lost. His essentialist principle is that if something is ever of a particular sort (such as 'cat') then it is always of that sort. Tib is not initially a cat.
Gist of Idea
Tib goes out of existence when the tail is lost, because Tib was never the 'cat'
Source
report of Michael Burke (Dion and Theon: an essentialist solution [1994]) by Theodore Sider - Four Dimensionalism 5.4
Book Reference
Sider,Theodore: 'Four Dimensionalism' [OUP 2003], p.162
A Reaction
This I take to be a souped up version of Wiggins, and I just don't buy that identity conditions are decided by sortals, when it seems obvious that sortals are parasitic on identities.