Economic definition of true love

Current Availability

I'm afraid that Ed is currently unavailable for dating at this time. Exceptions to this can be made if you have a Math(s) Ph.D.

That said, if you genuinely believe:

[math]p\left(You \cap The\,One \ne \{\empty\}\,|\,First\,Glance\right) \gg 0[/math]

then please stop by my office (F533) at the Haas School of Business (map) at your earliest convenience.

Future Availability

Please check back for updates.

True Love

Definition

Let [math]H[/math] denote the set of all entities (perhaps Humans, though we might also include dogs, cats and horses, according to historical precedent).

Let [math]T[/math] denote the set of pairs of individuals who have True Love, such that:

[math]\forall\{i,j\} \in T: \quad (i \succ_j h \quad \forall h \ne i,j) \and (j \succ_i h \quad \forall h \ne j,i), \quad h \in H \cap \{\emptyset\}[/math]

Note that:

• The definition employs strict preferences. A polyamorous definition might allow weak preferences instead.
• The union with the empty set allows for people who would rather be alone (e.g. Liz Lemmon/Tina Fey), provided that we allow a mild abuse of notation so that [math]i \succ_{\{\emptyset\}} h[/math]. The inclusion of the empty set is not necessary with weak preferences as then we can allow [math] i \succsim_i i[/math] without violating the definition of the preference relation.

The Existence of True Love

Can we prove that [math] T \ne \{\emptyset\}[/math] ?

The Brad Pitt Problem

Rational preferences aren't sufficient to guarantee that [math] T \ne \{\emptyset\}[/math].

Proof:

Recall that a preference relation is rational if it is complete and transitive:

1. Completeness: [math]\forall x,y \in X: \quad x \succsim y \;\or\; y \succsim x[/math]
2. Transitivity: [math]\forall x,y,z \in X: \quad \mbox{if}\; \; x \succsim y \;\and\; y \succsim x \;\mbox{then}\; x \succsim z[/math]

Also recall the definition of the strict preference relation:

[math]x \succ y \quad \Leftrightarrow \quad x \succsim y \;\and\; y \not{\succsim} x[/math]

Then suppose:

1. [math]\forall j \ne i \in H \quad i \succ_j h \quad \forall h\ne i,j \in H\quad\mbox{(Everyone loves Brad)}[/math]
2. [math]\{\emptyset\} \succ_i h \quad \forall h\ne i \in H\quad\mbox{(Brad would rather be alone)}[/math]

Then [math]T = \{\emptyset\}[/math] Q.E.D.