  The Swampland Program aims to address the question, "when does an effective
field theory model of quantum gravity have an ultraviolet complete embedding in
string theory?", and can be regarded as a bottom-up approach to investigations
of quantum gravity. An alternative top-down approach aim to explore the
imprints and the constraints imposed by the string theory dualities and
symmetries on the effective field theory representations of quantum gravity.
The most celebrated example of this approach is mirror symmetry. Mirror
symmetry was first observed in worldsheet contructions of string
compactifications. It was completely unexpected from the effective field theory
point of view, and its implications in that context were astounding. In terms
of the moduli parameters of toroidally compactified Narain spaces, mirror
symmetry can be regarded as arising from mappings of the moduli of the internal
compactified space. Spinor-vector duality, which was discovered in worldsheet
constructions of string vacua, is an extension of mirror symmetry that arises
from mappings of the Wilson line moduli, and provide a probe to constrain and
explore the moduli spaces of $(2,0)$ string compactifications. Mirror symmetry
and spinor-vector duality are mere two examples of a much wider symmetry
structure, whose implications are yet to be unravelled. A mapping between
supersymmetric and non-supersymmetric vacua is briefly discussed. $T$-duality
is another important property of string theory, and can be thought of as
phase-space duality in compact space. I propose that manifest phase-space
duality, and the related equivalence postulate of quantum mechanics, provide
the background independent overarching principles underlying quantum gravity.
