34
The War on Aging
they make these structures less elastic and thus more prone
to mechanical damage. The most promising first-generation
therapy to eliminate such cross-links is a molecule known as
ALT-711. [15] However, it breaks only one class of such link,
known as dicarbonyl bonds. [16] Numerous other classes have
been identified. [17] Worse, many are thermodynamically
much more stable than dicarbonyl bonds, giving reason to
doubt that non-toxic small molecules could ever cleave them.
More elaborate approaches (already under consideration, but
beyond the scope of this article) may thus be needed in order
to limit the abundance of crosslinks indefinitely.
THE ESCAPE VELOCITY TRANSITION
The above considerations constitute an acknowledgement
that aging will never be cured in the sense that a bacterial
infection is cured, i.e. entirely eliminated from the body.
Rather, it will be cured in the sense that malaria or AIDS
can presently be cured: it can be controlled very well given
access to appropriate medication whenever needed, but that
medication can never be confidently dispensed with forever.
It may not be clear to the reader, however, that what I have
said above allows even that degree of cure of aging.
The reason it does so can be summed up in one word:
bootstrapping. The second-generation therapies will not be
needed for at least two decades after the first-generation thera-
pies arrive, because that is how long it will take before the
seven deadly things return to the life-threatening level that
they attained before those therapies arrived. Thus, so long as
the second-generation therapies do indeed arrive within two
decades, we will be broadly in the same position as regards
mortality rates, as if they had arrived at the same time as the
first-generation. The same logic clearly extends to subsequent