Defining homologous genes is important in many evolutionary studies but raises obvious issues. Some of these issues are conceptual, and stem from our assumptions of how a gene evolves, others are practical, and depend on the algorithmic decisions implemented in existing software. Therefore, in order to make progress in the study of homology, both ontological and epistemological questions must be considered. In particular, defining homologous genes cannot solely be addressed under the classic assumptions of strong tree-thinking, according to which genes evolve in a strictly tree-like fashion of vertical descent and divergence and the problems of homology detection are primarily methodological. Gene homology could also be considered under a different perspective where genes evolve as ‘public goods’, subjected to various introgressive processes. In this latter case, defining homologous genes becomes a matter of designing models suited to the actual complexity of the data and how such complexity arises, rather than trying to fit genetic data to some a priori tree-like evolutionary model, a practice that inevitably results in the loss of much information. Here we show how important aspects of the problems raised by homology detection methods can be overcome when even more fundamental roots of these problems are addressed by analysing ‘public goods thinking’ evolutionary processes through which genes have frequently originated. This kind of thinking acknowledges distinct types of homologs, characterised by distinct patterns, in phylogenetic and non phylogenetic unrooted or multi-rooted networks. In addition, we define “family resemblances” to include genes that are related through intermediate relatives, thereby placing notions of homology in the broader context of evolutionary relationships. We conclude by presenting some pay-offs of adopting such a pluralistic account of homology and family relationship, that expands the scope of evolutionary analyses beyond the traditional, yet relatively narrow focus allowed by a strong tree-thinking view on gene evolution.