Science is a process
- Scientific ideas are developed through reasoning.
Inferences are logical conclusions based on observable facts. Much of
what we know from scientific study is based on inferences from data, whether
the object of study is a star or an atom. No person has ever seen
inside an atom, yet we know, by inference, what is there. Atoms have been
disassembled and their components determined. The history of life on Earth
has likewise been inferred through multiple lines of evidence.
No person has ever looked inside an atom but we know what is there.
No person has lived through deep time but we know it has occurred.
In the marketplace of ideas, the simplest explanation has the advantage. This principle is referred to as parsimony. Consider these observations:
- Scientific claims are based on testing explanations against observations
of the natural world and rejecting the ones that fail the test.
Scientific explanations are evaluated using evidence from the natural world.
That evidence may come from various sources: a controlled lab experiment, a
study of anatomy, or recordings of radiation from outer space, to name just a
few. Explanations that don't fit the evidence are rejected or are modified and
- Scientific claims are subject to peer review and replication.
Peer review is an integral part of genuine scientific enterprise and goes
on continuously in all areas of science. The process of peer review includes
examination of other scientists' data and logic. It attempts to identify
alternative explanations, and attempts to replicate observations and experiments.
- A close look at snails, nautiloids, squids, octopuses and cuttlefish
reveals the basic similarity of the body form of each (see below).
- The shell of a nautilus and its extinct relatives, the ammonites,
is very similar to the shell of a snail.
- The tentacles of an octopus, when carefully examined, can be seen
to be a modified snail's foot.
Common ancestry is the parsimonious explanation for the similarities between this octopus and its kin.
- The stomachs of all members of this group have the same arrangement
One possible explanation is that these animals have independently acquired
equivalent organs through a remarkable series of coincidences, but the
most likely explanation is that these animals inherited similar organs
through common ancestry. That is parsimony.
There is no such thing as "THE Scientific Method."
If you go to science fairs or read scientific journals, you may get
the impression that science is nothing more than "question-hypothesis-procedure-data-conclusions."
But this is seldom the way scientists actually do their work. Most scientific
thinking, whether done while jogging, in the shower, in a lab, or while
excavating a fossil, involves continuous observations, questions, multiple
hypotheses, and more observations. It seldom "concludes" and never "proves."
Scientists working in the field to excavate a fossil.
Putting all of science in the "Scientific Method" box, with its implication
of a white-coated scientist and bubbling flasks, misrepresents much of
what scientists spend their time doing. In particular, those who are involved
in historical sciences work in a very different way one in which
questioning, investigating, and hypothesizing can occur in any order.
Theories are central to scientific thinking.
This is a false science stereotype.
Theories are overarching explanations that make sense of some aspect of
nature, are based on evidence, allow scientists to make valid predictions,
and have been tested in many ways. Theories are supported, modified, or
replaced as new evidence appears. Theories give scientists frameworks
within which to work. Major theories of science, such as the cell theory,
gravitational theory, evolutionary theory, and particle theory, are all
big ideas within which scientists test specific hypotheses.
The scientific definition of "theory" should not be confused with the
way the term is commonly used to mean a guess or a hunch. In science,
a theory means much more and is far more well-founded. The "Theory of
Evolution" is an evidence-based, internally consistent, well-tested explanation
of how the history of life proceeded on Earth not a hunch. Understanding
the role of theory in science is essential to scientists and vital to
the informed citizen.