Book One -- The things that sustain and support the entire body, and what braces and attaches them all. [the bones and the ligaments that interconnect them] | Chapter 27 On the Digits of the Hand

The fingers are rightly made up of three bones each

It was stated in the previous chapter that all the digits of the hand (in figs. 1 and 2, ch. 25, the bones of the thumb are marked A, B, C, those of the index finger D, E, F; the system applies also to the others) consist of three bones each 4 — they are called internodes, joints, and acies 5 , or also fa/laggoj, 6 skutali/dej, 7 and ko/nduloi. 8 These bones are hard and dense, but not entirely without marrow (as we have sometimes warned contrary to Galen’s view). 9 For besides the fact that they are somewhat spongy above and below like epiphyses, each has a rather large cavity provided to hold marrow as in the metacarpal bones. I believe it is no secret that we require the bones of the fingers for strength of action in grasping things, and we need many of them because of the various motions which the hands perform and the diversity of things which are grasped by them. 10 Next, it is very easily inferred that it was altogether practical for the fingers that there are neither more bones nor fewer than three, because if there were more than that number, not only


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would they serve no purpose (we all can do a great deal with three bones), they would also interfere with the complete and effective extension of the fingers, making it less strong than it is. For things constructed of more parts more readily become fatigued, tired, and deprived of their strength than those fashioned of fewer, chiefly because all the pieces, once joined and attached together (like the carpal bones), are unable to be maintained in all of their functions. But if the fingers were made up of fewer bones, we would be unable to move the fingers into such various and contrasting shapes. So the number of three bones is sufficient that they be moved in a number of ways and avoid a liabitity to be hurt.



Book One -- The things that sustain and support the entire body, and what braces and attaches them all. [the bones and the ligaments that interconnect them] | Chapter 27 On the Digits of the Hand