‘occupies spatial region’ definition and mereological change

[gregfowlerphd]

Describe the (possible) bug

It’s possible this issue is an artifact of the difficulty of dealing with time in OWL, but I think the definition for occupies spatial region implies that I needn’t occupy the spatial region (SR) jointly “taken up” by my head, torso, legs, arms, etc. at the present time. Allow me to explain.

The definition reads:

b occupies spatial region r =Def b is an independent continuant that is not a spatial region & r is a spatial region & there is some time t such that every continuant part of b occupies some continuant part of r at t and no continuant part of b occupies any spatial region that is not a continuant part of r at t

Let b be me and r be SR. Is there any time t such that every continuant part of me occupies some continuant part of SR at t? Well, by the definition of ‘continuant part of’--

b continuant part of c =Def b and c are continuants & there is some time t such that b and c exist at t & b continuant part of c at t

--a skin cell (SC) that sloughed off my arm yesterday continuant part of me, since there’s a time t (e.g., some time yesterday before the sloughing occurred) such that SC continuant part of me at t. However, SC does not occupy any continuant part of SR at the present moment, nor need there be any time at which SC occupies some continuant part of SR. Hence, there need be no time t such that every continuant part of me occupies some continuant part of SR at t, in which case the occupies spatial region definition has the consequence that I needn’t occupy SR, the spatial region jointly “taken up” by my head, torso, legs, arms, etc. at the present time.

Is this an intended implication of the definition? It’s certainly odd, but given that the continuant part of definition itself has the odd implication that SC continuant part of me (despite having sloughed off yesterday), I’m not sure that shows anything.