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ABSTRACT A review of the state of knowledge of the physics of the static mode seeding hypothesis for convective clouds is presented. The central thesis of the review is that the results of past experimental work are diverse but valid and that credibility of the science depends on understanding the phy- sical reasons for the diverse results. Areas of uncertainty and conflicts in evidence associated with the statement of physical hypothesis, the con- cept of seedability, the seeding operation and the chain of physical events following seeding are highlighted to identify what issues need to be resolved to further progress in precipitation enhancement research and application. It is concluded that the only aspect of static seeding that meets scien- tific standards of cause and effect relationships and repeatability is that glaciogenic seeding agents can produce distinct "seeding signatures" in clouds. However, the reviewer argues that a body of inferential physi- cal evidence has been amassed that provides a better understanding of which clouds are seedable (susceptible to precipitation enhancement by artificial seeding) and which are not, even though the tools for recognizing and pro- perly treating them are imperfect. In particul ar, the inferred evidence appears to support the claims of physical plausibility for the positive statistical results of the Israeli experiments. It is suggested that future work continue to be designed for physical understanding and evaluation through comprehensive field studies and numerical modeling. Duplicating the Israeli experiments in another loca- tion should receive high priority but, in general, future experiments should move upscale from cumulus congestus to convective complexes. In doing so, a new, more complex physical hypothesis that accounts for cloud- environment and microphysical-dynamical interactions and their response to seeding will have to be developed.