Subsequent to the arrangement of Aristotle's works by scholars at Alexandria in the first century CE, a number of his treatises were referred to as τὰ μετὰ τὰ φυσικά (ta meta ta fysika; literally, "the [writings] after the Physics"). This is the origin of the title for collection of treatises now known as Aristotle's Metaphysics. Some have interpreted the expression "τὰ μετὰ τὰ φυσικά" to imply that the subject of the work goes "beyond" that of Aristotle's Physics or that it is metatheoretical in relation to the Physics. But others believe that "τὰ μετὰ τὰ φυσικά" referred simply to the work's place in the canonical arrangement of Aristotle's writings, which is at least as old as Andronicus of Rhodes or even Hermippus of Smyrna. Within the Aristotelian corpus itself, the metaphysical treatises are referred to as τὰ περὶ τῆς πρώτης φιλοσοφίας (literally, "the [writings] concerning first philosophy"); "first philosophy" was what Aristotle called the subjects of metaphysics. (He called the study of nature or natural philosophy "second philosophy" (Metaphysics 1037a15).)
It is notoriously difficult to specify the date at which Aristotle wrote these treatises as a whole or even individually, especially because the Metaphysics is, in Jonathan Barnes' words, "a farrago, a hotch-potch", and more generally because of the difficulty of dating any of Aristotle's writings.
In the manuscripts, books are referred to by Greek letters. The second book was given the title "little alpha," apparently because it appears to have nothing to do with the other books (and, very early, it was supposed not to have been written by Aristotle) or, although this is less likely, because of its shortness. This, then, disrupts the correspondence of letters to numbers, as book 2 is little alpha, book 3 is beta, and so on. For many scholars, it is customary to refer to the books by their letter names. Thus book 1 is called Alpha (Α); 2, little alpha (α); 3, Beta (Β); 4, Gamma (Γ); 5, Delta (Δ); 6, Epsilon (Ε); 7, Zeta (Ζ); 8, Eta (Η); 9, Theta (Θ); 10, Iota (Ι); 11, Kappa (Κ); 12, Lambda (Λ); 13, Mu (Μ); 14, Nu (Ν).
It is possible that Aristotle did not write the books in the order in which they have come down to us; their arrangement is due to later editors, and there is little reason to think that it reflects how Aristotle himself would have arranged them. Based on a careful study of the content of the books and of the cross-references within them, W.D. Ross concluded that books A, B, Γ, E, Z, H, Θ, M, N, and I "form a more or less continuous work", while the remaining books were inserted into their present locations by later editors. However, Ross cautions that books A, B, Γ, E, Z, H, Θ, M, N, and I — with or without the insertion of the others — do not constitute "a complete work".