 Alan Sidelle (1989, 1991, 1998) argues that while stuff exists, there are no things which exist and actually have the essences we believe they do. In 1998 he argues that we should regard the unraveling of a sweater, or the chopping down of a tree, not as substantial changes in which things cease to be, but rather as accidental changes in underlying, persisting stuff (compare also Needham 2010):