Philosophers have proposed many accounts of biological function. A coarse-grained distinction can be made between backward-looking views, which emphasise historical contributions to fitness, and forward-looking views, which emphasise the current contribution to fitness or role of a biological component within some larger system. These two views are often framed as being incompatible and conflicting with one another. The emerging field of synthetic biology, which involves applying engineering principles to the design and construction of biological systems, complicates things further by adding (...) intentional design as a source of function. In the current study we explored how biology experts and novices think about function in the context of single-celled, multi-celled, and synthetic organisms. We also explored the extent to which each group were function pluralists, and if they were function pluralists, which accounts of function tended to be endorsed together. The results showed a surprising degree of similarity between experts and novices in most contexts, although certain differences were apparent. Most surprisingly, we found evidence not only of function pluralism in both groups, but pluralism between backward-looking and forward-looking accounts. We discuss these findings in the context of the philosophical debate on function and consider the practical implications for public acceptance of synthetic biology. First, we argue that philosophers of biology should re-examine the purported incompatibility between accounts of function. Second, we argue that due to the introduction of an intentional aetiology in synthetic biology, there may be an inherent conflict between the views of experts and novices when thinking about synthetic biology. (shrink)