"This is Biology, The Science of the Living World", Ernst Mayr, 1997
ISBN 0-674-88468-X, QH307.2.M39

"The demarcation between science and theology is perhaps easiest, because
scientists do not invoke the supernatural to explain how the natural world
works, and they do not rely on divine revelation to understand it." (p33)

"If we say that a particular mutation is random, it does not mean that a
mutation at that locus could be anything under the sun but merely that it
is unrelated to any current needs of the organism or is not in any way
predictable." (p 69)

Mayr on Origin of Life

"The subject of life's origin is highly complex, but it is no longer the
mystery it once was, in the early post-Darwinian period.  In fact, there
is no longer any fundamental difficulty in explaining, on the basis of
physical and chemical laws, the origin of life from inanimate matter."
(p 179)

Mayr on Chance/Necessity

"From the Greeks to the nineteenth century there was a great controversy
over the question whether changes in the world are due to chance or
necessity.  It was Darwin who found a brilliant solution to this old
conundrum: they are due to both.  In the production of variation chance
dominates, while selection itself operates largely by necessity." (p 189)

Mayr on Evolutionary progress

"There simply is no indication in the history of life of any universal
trend to, or capacity for, evolutionary progress.  Where seeming progress
is found, it is simply a byproduct of changes effected by natural selection."
(p 198)

Mayr on Species

"The word 'species' is applied to three very different objects or
phenomena: (1) the species concept, (2) the species category, and 
(3) species taxa.  Endless confusion in the literature has resulted
from the failure of some authors to discriminate among these three very
different meanings of the words 'species.'

The species concept is the biological meaning or definition of the word
"species."  The species category is a particular rank in the Linnaean
hierarchy - the traditional hierarchy in which organisms are placed.
Each rank in this hierarchy (such as species, genus, order, and so on)
is referred to as a category.  To determine whether a population 
belongs in the species category, one tests it against species definition.
Species taxa are particular populations or groups of populations that
comply with the species definition; they are particulars ("individuals")
and this cannot be defined, only described and demarcated against each
other." (p 133)

Mayr on Philosophy of Science

"Although philosophers of science often state that their methodological
rules are merely descriptive and not prescriptive, many of them seem to
consider it their task to determine what scientists *should* be doing.
Scientists usually pay no attention to this normative advice but rather
choose that approach which (they hope) will lead most quickly to results;
these approaches may differ from case to case.

Perhaps the greatest failing of the philosophy of science, until only
a few years ago, was that it took physics as the exemplar of science."
(p36).

To me the need for clear definitions is so obvious that I have never
been able to understand why so many philosophers have been opposed to
giving definitions.  Popper, one of the most adamant opponents of
definitions, revealed in his autobiography, Uneded Quest (1974),
why he held this view. ... Popper here reveals what he is opposed to.
It is the game logicians to lay down definitions of words and then to
operate in syllogisms with these." (p59)

It is my feeling as a practicing scientist that philosophers should
give up their antipathy to definitions and should test by precise 
definitions whether or not the terms they use refer to a single object
or a heterogeneous mixture.  This would put an end to a considerable
number of controversies in the philosophical literature. (p60)

"There is a deplorable ignorance among most people of even the simplest
facts of science.  For example, writer of writer still states that he
cannot believe that the eye is the result of accidents.  What this
statment reveals is that the writer has no understanding of natural
selection, which is an antichance - rather than an accidental - process."
(p38)

Mayr on Predictions

"For example, philosophers of science since the days of the logical
positivists have placed great stress on the capacity of theories to
make predictions.  The better a theory is, the more correct the
predictions it permits.  Prediction in this context means logical
prediction: provided that such and such a constallation of factors
exists, one can expects such and such an outcome to occur.  This use
of prediction in logic is different from the everyday use of the word
"prediction," which means being able to foretell the future.  Foretelling
the future is *chronological prediction*.  Many authors (including
myself in the past) have confused the two kinds of prediction." (p53)

"Predictions in biology are at best probabilistic, owing to the
great variability of most biological phenomena and owing to the
occurence of contigencies and multiplicity of interacting factors that
affect the course of events.  For the biologist, it is not so important
that his theory survive the test of prediction, it is more important
that his theory is useful in solving problems." (p54)

Mayr on Scientific Progress

Throughout the philosophy of science, one finds widespread objection
to the notion of scientific progress, which Kitcher (1993) has referred
to as the Legend." ... My confession that I adhere to the Legend will
undoubtedly make these critics consider me old-fashioned. (p 80)

Most of those who have attacked the notion of scientific progress have
been phiolophers or other nonscientists who simply do not have the
expertise to be able to evaluate whether or not there has been any
real progress in our understanding.  Everything I know about science
leads me to disagree with the claims of these critics. (p82)

Mayr on "junk" DNA

"To assume that all of this DNA is merely an unwanted byproduct ("junk")
of various molecular processes is not a palatable solution for a
Darwinian.  ... My guess is that some of the DNA is indeed unselected (
or not yet counter-selected) byproduct of molecular process, but that
other components are part of the complex regulatory machinery of the
genome." (p105)

"Even those who continue to use the word selection, which presumably 
will be the majority of evolutionists, should never forget that it 
really means nonrandom elimination, and that there is no selection force
in nature." (p 189)

"In short, there are multiple possible solutions for many evolutionary
challenges, even though all of them are compatible with the Darwinian
paradigm.  The lesson one must learn from this pluralism is that 
evolutionary biology sweeping generalizations are rarely correct.  Even
when something occurs "usually", this does not mean it must happen always.
(p206).

Mayr on how Biology advances

The picture of theory change that Kuhn painted in 1962 was congenial
to the essentialistic thinking of physicalists, but it was incompatible
with the thinking of a Darwinian.  It is therefore not surprising that
the Darwinians favored an entirely different conceptualization for
theory change in biology, usually referred to Darwinian evolutionary
epistemology.

...

The principal thesis of Darwinian evolutionary epistemology is that
science advances very much as does the organic world - through the Darwinian
process.  Epistemological progress thus is characterized by variation
and selection.  More precisely, "More robust idea or ideas with greater
verisimilitude or greater explanatory power or greater problem solving
ability etc., survive better from one generation to the next in struggle
for acceptance."  (p99)

...

"The variation, for instance, among the various theories is not caused
by chance, as is genetic variation, but by the reasoning of the promoters
of these theories. ... the source of is of little consequence for the
Darwinian process. ... Hence, it is irrelevant whether the variation is
produced by chance or not." (p100)

The transmission from generation to generation in evolutionary epistemology
is cultural transmission, something very different from genetic transmission,
... (p100).