Philosophers dilemma. Neato layout.

## "It encodes the so-called philosophers dilemma.  Neato pretty much approximates the way how humans would layout the graph." Contributed by Manfred Jeusfield.
## Command to generate the layout: "neato -Tpng thisfile > thisfile.png" 


digraph PhiloDilemma {
fontname="Helvetica,Arial,sans-serif"
node [fontname="Helvetica,Arial,sans-serif"]
edge [fontname="Helvetica,Arial,sans-serif"]
layout=neato
node [shape=box];  bec3; rel3; bec2; rel2; acq2; acq3; bec1; rel1; acq1;
node [shape=circle,fixedsize=true,width=0.9];  hu3; th3; ri3; ea3; hu2; th2; ri2; ea2; hu1; th1; ri1; ea1;
ri3->acq2;
ri3->acq3;
hu3->acq3;
bec3->hu3;
th3->bec3;
rel3->th3;
rel3->ri3;
ea3->rel3;
acq3->ea3;
ri2->acq1;
ri2->acq2;
hu2->acq2;
bec2->hu2;
th2->bec2;
rel2->th2;
rel2->ri2;
ea2->rel2;
acq2->ea2;
ri1->acq3;
ri1->acq1;
hu1->acq1;
bec1->hu1;
th1->bec1;
rel1->th1;
rel1->ri1;
ea1->rel1;
acq1->ea1;

overlap=false
label="PetriNet Model PhiloDilemma\nExtracted from ConceptBase and layed out by Graphviz "
fontsize=12;
}