First Principles - Sustainable Design: The Science of Sustainability and Green Engineering - page 33

Figure 2.1 The cascade of
sciences that lead to a sustainable
decision. Each lower box depends
on the quality of every box above
it, so that uncertainties and
variability must be considered
with each progression.

Physics
Thermodynamics
Motion

Chemistry
Reactions
Solutions
Kinetics & Equilibrium

Biology
Cellular
Functions
Structures

Microbiology
Processes

Medicine
Treatment
Epidemiology

Ecology
Functional & Structural

Engineering
Treatment
Prevention

Sustainable Design

Policies Management Decisions

help to shape the first step, awareness . This step is messy and tries to reach una-
nimity, or at least consensus. Physics is more comfortable with unanimity. It is
best if all credible physicists agree on something. For example, most agree on the
properties of heat flux, mass balance, and other thermodynamic principles. They
may hold diverse opinions as to why thermodynamic processes occur from an
elementary, subatomic perspective, but they agree on the empirical explanations
of the processes. The same goes for chemistry. We agree about electronegativ-
ity, polarity, and reduction-oxidation, even though we do not necessarily agree
about the role of quantum mechanics in these processes. Biology also requires
rigorous application of physical and chemical principles. As such, it is a “derived”
science, with greater uncertainty and variability than those of empirical physics