 The above-cited passage from the Topics, and Aristotle’s general practice, help to determine and explain the title of the Theophrastean treatise Diels believed to be foundational: it should be Physikai Doxai, i.e., ‘Tenets in [the various fields of] Natural Philosophy’. And one of the rare extant fragments of this treatise not only proves (because of the formulation in Greek of the title as quoted) that this title really is ‘Physical Tenets’, but also demonstrates that such tenets were criticized according to the rules of dialectic. Theophrastus, we are informed, cited a tenet of Plato’s and then formulated ‘the objections’ against it. The Greek word for ‘objections’ found in this fragment, enstaseis, is a technical term in Aristotle’s Topics. Physical tenets are tenets, or theses, in the fields of natural philosophy in the largest sense, ranging from the principles, via cosmology, astronomy and meteorology etc., to human psychology (including philosophy of mind), biology, and even nosology or the theory of diseases. Physical tenets are not only formulated by physikoi, natural philosophers, but also by physicians and astronomers. Aëtius indeed contains a number of  medical[4]  and astronomical doxai, the oldest of which may derive from sources that can perhaps be attributed to some of Aristotle’s collaborators. (For further reading on this topic, see Mansfeld 1990, 1992, 1998, 2016a, Mansfeld &amp; Runia 1997, Runia 1999a, Runia 2004, with criticism in Zhmud 2001 and rejoinder in Mansfeld 2002.) 