Page 302 - J. C. Turner "History and Science of Knots"
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On Theories of Knots                    293

        Knot we obtain a Right-Hand Trefoil; but in the case of a "closed" everted
        Overhand Half Knot we obtain a closed ring with a full (left-hand) screw turn
       in the string (an Un-Knot in the "classical knot theory"). Hence we obtain
       two vastly different knots, even in the "classical knot theory". Of course, the
        "classical knot theorist" may say that the everting process should take place
       after closure, but not only is such an excuse obvious nonsense (since by doing
       so we delete an existing crossing and create a new one; hence if we allow
       closure before the completion of braiding procedures, we may as well start
       with a closed string-run in the form of a circle (their Un-Knot); it moreover
       results in the loss of the relationship between an Overhand Half Knot and its
       everted form.'


           Schaake goes on to discuss many aspects of the construction of braids,
       using examples from basic knots such as the 4-crossing knots (see the 16 grid
       diagrams shown above, and the comments given upon them), the Overhand
       Half Knots, composite Trefoil Knots, Strangle Knots and Constrictor Knots.
       His aims are to uncover [quote] `the Facts about some REAL KNOTS'.

       9. Summary

       In this Chapter we have tried to present a picture of fields of knot studies which
       generally are unknown to, or given only a sideways glance by, mathematical
       knot theorists. We believe that if these other fields are added to that which
       concerns topological knot theorists, then we shall have a more correct purview
       for a balanced and useful theory of knots.* A much wider range of problems
       will then present themselves to mathematicians for solution.
           We began this Chapter by discussing the questions `What is a Science?
       and `Is there a Knot Science?'. Let us end with the same questions. Some
       might ask-perhaps with justification-Does it matter? What's in a name?
       Philosophers have argued about vaguer concepts, sometimes for hundreds of
       years (for example `the number of angels that can stand upon a pinhead'; we
       maintain that our topic stands firmer than that one.) We might also remark
       that deciding whether a subject is, or is not, a Science, is one that exercises
       deeply the minds of Vice-Chancellors of Universities; because the magnitudes
       of their annual subject grants depend heavily upon the decision. The Sciences
       are much favoured over the Arts, for purposes of allocating grants.
       an outer and an inner surface, and two lateral faces. Using grid diagrams he can define
       `evert equivalency' for these braids.
       *Gauss, the father of knot theory, would seem to have recognized this, when, in January
       1833, he wrote that the major task for knot theorists would be to count the `different
       windings' [Umschlingungen] of two closed or infinite curves, and he placed the problem in
       `the boundary field between'[Grenzgebiet] Geometria Situs and Geometria Magnitudinis.
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