Original: More abstract and theoretical arguments for the plausibility of the emergence of metabolism without the presence of genes include a mathematical model introduced by Freeman Dyson in the early 1980s and Stuart Kauffman's notion of collectively autocatalytic sets, discussed later in that decade.
Simplified: Freeman Dyson introduced a mathematical model in the 1980s. Stuart Kauffman developed the notion of autocatalytic sets, which was discussed later in that decade.