Is Rabc a Valid Formula in Predicate Logic?

[pivoxa15]

In predicate logic

Let R = Run towards

a=Adam
b=Betty
c=Celsi

Would a formula like Rabc make sense?

What would it read?

Would Rabc = Rab & Rac

 

[MathematicalPhysicist]

if b and c are in the same location then it makes sense, but otherwise it doesnt.
an example of three place predicate is "between", x is between y and z, here you can't divide it into Bxy&Bxz cause it doesn't make sense.

 

[pivoxa15]

if b and c are in the same location then it makes sense, but otherwise it doesnt.

b could be north of a and c is north east of a. Then a could be running towards both of them without b and c both in the same location.

...an example of three place predicate is "between", x is between y and z,

So if B is between

then you could have Bxyz (i.e. a forumla with 3 subjects) which translates to x is between y and z. In this case it is necessary to have three subjects after B, anything else won't make sense.

 

[pivoxa15]

Is it true that in general if Rabc

than it can be read (a R b and c)

i.e Adam 'is running towards' Betty and Celsi.

Adam 'is in between' Betty and Celso.