  Assembly Theory (AT) was developed to help distinguish living from non-living
systems. The theory is simple as it posits that the amount of selection or
Assembly is a function of the number of complex objects where their complexity
can be objectively determined using assembly indices. The assembly index of a
given object relates to the number of recursive joining operations required to
build that object and can be not only rigorously defined mathematically but can
be experimentally measured. In pervious work we outlined the theoretical basis,
but also extensive experimental measurements that demonstrated the predictive
power of AT. These measurements showed that is a threshold in assembly indices
for organic molecules whereby abiotic chemical systems could not randomly
produce molecules with an assembly index greater or equal than 15. In a recent
paper by Hazen et al [1] the authors not only confused the concept of AT with
the algorithms used to calculate assembly indices, but also attempted to
falsify AT by calculating theoretical assembly indices for objects made from
inorganic building blocks. A fundamental misunderstanding made by the authors
is that the threshold is a requirement of the theory, rather than experimental
observation. This means that exploration of inorganic assembly indices
similarly requires an experimental observation, correlated with the theoretical
calculations. Then and only then can the exploration of complex inorganic
molecules be done using AT and the threshold for living systems, as expressed
with such building blocks, be determined. Since Hazen et al.[1] present no
experimental measurements of assembly theory, their analysis is not
falsifiable.
