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Definitions of philosophical terms


The state of awareness that only material phenomena can be known, that certainty in any matter cannot be assumed, and that the existence of supreme beings, gods and other supernatural phenomena, cannot be known for sure. Invented by Thomas Huxley in 1869, soon after his head to head with the religious bigots who opposed Darwin's Theory of Evolution. Agnosticism is a useful counter against religious arguments, since it effectively shifts the onus of proof, and therefore admissability of argument, onto those who seek to introduce extraneous non-factual elements in an attempt to override logical and rational debate.


Constructivist epistemology is that knowledge is obtained subjectively in a world of meanings created by individuals. Its ontology is that what exists is that which people perceive to exist. Constructivist methodology includes the objective investigation of the individual worlds of perception, and emphasises specificity and subjectivity, in contrast to positivism, which emphasises replicability and truth.


From Latin deus ('god'), deism rejects revelation and authority as reliable for obtaining religious understanding, and asserts that a process of rational thought and observation of nature are all that is required with regard determining whether a single creator of the universe is a tenable proposition. Deism was prevalent among the 18th century revolutionary leaders, who, seeking to change the status quo, were motivated to reject the dogma of organised religion as a political tool of control and oppression.


The philosophical tradition of empiricism is that we know through experience. The ontology (defining what can be known) of empiricism is that the things we experience are the things that exist. The empiricist methodology simply requires the presentation of experienced facts.


Epistemology combines the Greek words for 'knowledge' (epistēmē) + 'study of' (logos), and is the study of knowledge and attempts to define where belief can be justified. 'How do we know what we think we know?' and in what way are concepts such as truth and belief justified as derivatives of that 'knowledge'.


Problem solving and investigative techniques based more on experience and commonsense or intuition, rather than confirmed facts. When a statement is prefixed by 'as a rule of thumb', 'my educated guess is', or simply 'experience dictates', then heuristics is being applied to move an argument forward.

Heuristics is used in engineering and computing to permit strategies for utilising information for problem solving.

Occam's Razor

Named after William of Ochkam, c. 1287 - 1347, an English Franciscan friar, known for his philosophical writings. Where there are competing hypotheses, the one which presents the fewest required premises should be considered more likely to be correct.

A famous example is the heliocentric versus Ptolemaic solar system models. Both work, but placing the sun at the centre of the solar system, and having all planetary bodies, including the Earth, in orbit around it, requires far simpler mathematics and other explanations than the wheels within wheels circus of Ptolemy.

The conclusions based on Occam's Razor cannot be taken as proofs, but only as working hypotheses, and as a tool for 'getting on with it', in the absence of conclusive data or evidence.


The study of the nature of existence or reality, and in particular sentient existence, or 'being'. Arising from metaphysics, ontology is today a serious system within philosophy for the debate about the existence of entities, and the creation of relationship hierarchies.


Positivism is the basis for natural science and neo-classical economics. The philosophical tradition of positivism extends empiricism's assertion that we know through experience to include the requirement that such experience be firmly established as verifiable evidence. The positivist ontology is that of agreed evidence, and the methodology is verifying factual statements.


Adjective for a person or for the view or actions which favour the return to a previous political situation (status quo ante). Conservatives or the right-wing prior to a change of order may develop into reactionaries, in order to re-establish the conditions which favour the values which they view have been lost.

Straw Man

A political and philosophical trick whereby an impression is given that the arguments of an opponent are being refuted in a discourse, but in reality arguments not proposed by the opponents are being refuted. The straw man metaphor refers to the show of knocking down an opponent, who is in reality a straw mannequin, not the real person.


The epistemology of structuralism is that the world of appearances does not necessarily reveal the world of mechanisms. Structuralist ontology asserts that what really exists, such as the forces shaping the world we experience, and its structures, cannot be directly observed. They are conceived through thought only. Structuralist methodology develops theories to account for observations, but there can be no way to test their validity, due to lack of direct evidence of their existence.

Content © Andrew Bone. All rights reserved. Created : January 8, 2015 Last updated :June 12, 2016

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People write to me that evolution is only a theory. Well, it is not a theory. Evolution is as solid a historical fact as you could conceive. Evidence from every quarter. What is a theory is whether natural selection is the mechanism and the only mechanism. That is a theory. But the historical reality that dinosaurs led to birds and mammals produced whales, that's not theory.

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