Inverse-square orbits in Newton's \(Principia\) and twentieth-century commentary thereon (Q1593672)

There has been much debate about whether or not Isaac Newton rigorously proved the theorem in the \textit{Principia} that if a body moves around a force centre under an inverse square law of attraction, then it describes a conic section in its orbit. The author restates his case that Newton only establishes which section is described, the type of curve being assumed. He also reviews recent historical writings in which Newton's proof is claimed to be adequate.